Finish removing //flutter/tonic (#2917)

This pulled a refactoring of how we keep track of the primary threads.

BUILD.gn

@@ -13,7 +13,7 @@ group("flutter") {
       "//flutter/glue",
       "//flutter/lib/ui",
       "//flutter/snapshotter",
-      "//flutter/tonic",
+      "//lib/tonic",
     ]
   } else {
     deps = [

tonic/BUILD.gn → common/BUILD.gn

@@ -2,20 +2,15 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-source_set("tonic") {
+source_set("common") {
   sources = [
-    "dart_state.cc",
-    "dart_state.h",
+    "settings.cc",
+    "settings.h",
+    "threads.cc",
+    "threads.h",
   ]
 
   deps = [
-    "//dart/runtime/bin:embedded_dart_io",
     "//lib/ftl",
   ]
-
-  public_deps = [
-    "//dart/runtime:libdart",
-    "//dart/runtime/vm:libdart_platform",
-    "//lib/tonic",
-  ]
 }

common/README.md

+Flutter Common
+==============
+
+The bottom of the dependency graph for Flutter. Useful for static constants.
+Please don't put too much in here.

sky/engine/platform/exported/sky_settings.cc → common/settings.cc

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "flutter/sky/engine/public/platform/sky_settings.h"
+#include "flutter/common/settings.h"
 
 #include <memory>
 
@@ -11,19 +11,19 @@
 namespace blink {
 namespace {
 
-SkySettings* g_settings = nullptr;
+Settings* g_settings = nullptr;
 
 }  // namespace
 
-const SkySettings& SkySettings::Get() {
+const Settings& Settings::Get() {
   FTL_CHECK(g_settings);
   return *g_settings;
 }
 
-void SkySettings::Set(const SkySettings& settings) {
+void Settings::Set(const Settings& settings) {
   FTL_CHECK(!g_settings);
-  g_settings = new SkySettings();
+  g_settings = new Settings();
   *g_settings = settings;
 }
 
-} // namespace blink
+}  // namespace blink

sky/engine/public/platform/sky_settings.h → common/settings.h

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef SKY_ENGINE_PUBLIC_PLATFORM_SKY_SETTINGS_H_
-#define SKY_ENGINE_PUBLIC_PLATFORM_SKY_SETTINGS_H_
+#ifndef FLUTTER_COMMON_SETTINGS_H_
+#define FLUTTER_COMMON_SETTINGS_H_
 
 #include <stdint.h>
 
@@ -12,7 +12,7 @@
 
 namespace blink {
 
-struct SkySettings {
+struct Settings {
   bool enable_observatory = false;
   // Port on target will be auto selected by the OS. A message will be printed
   // on the target with the port after it has been selected.
@@ -24,10 +24,10 @@ struct SkySettings {
   std::string temp_directory_path;
   std::vector<std::string> dart_flags;
 
-  static const SkySettings& Get();
-  static void Set(const SkySettings& settings);
+  static const Settings& Get();
+  static void Set(const Settings& settings);
 };
 
 }  // namespace blink
 
-#endif  // SKY_ENGINE_PUBLIC_PLATFORM_SKY_SETTINGS_H_
+#endif  // FLUTTER_COMMON_SETTINGS_H_

common/threads.cc

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "flutter/common/threads.h"
+
+#include <utility>
+
+namespace blink {
+namespace {
+
+Threads* g_threads = nullptr;
+
+}  // namespace
+
+Threads::Threads() {}
+
+Threads::Threads(ftl::RefPtr<ftl::TaskRunner> gpu,
+                 ftl::RefPtr<ftl::TaskRunner> ui,
+                 ftl::RefPtr<ftl::TaskRunner> io)
+    : gpu_(std::move(gpu)), ui_(std::move(ui)), io_(std::move(io)) {}
+
+Threads::~Threads() {}
+
+const ftl::RefPtr<ftl::TaskRunner>& Threads::Gpu() {
+  return Get().gpu_;
+}
+
+const ftl::RefPtr<ftl::TaskRunner>& Threads::UI() {
+  return Get().ui_;
+}
+
+const ftl::RefPtr<ftl::TaskRunner>& Threads::IO() {
+  return Get().io_;
+}
+
+const Threads& Threads::Get() {
+  FTL_CHECK(g_threads);
+  return *g_threads;
+}
+
+void Threads::Set(const Threads& threads) {
+  FTL_CHECK(!g_threads);
+  g_threads = new Threads();
+  *g_threads = threads;
+}
+
+}  // namespace blink

common/threads.h

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef FLUTTER_COMMON_THREADS_H_
+#define FLUTTER_COMMON_THREADS_H_
+
+#include "lib/ftl/tasks/task_runner.h"
+
+namespace blink {
+
+class Threads {
+ public:
+  Threads();
+  Threads(ftl::RefPtr<ftl::TaskRunner> gpu,
+          ftl::RefPtr<ftl::TaskRunner> ui,
+          ftl::RefPtr<ftl::TaskRunner> io);
+  ~Threads();
+
+  static const ftl::RefPtr<ftl::TaskRunner>& Gpu();
+  static const ftl::RefPtr<ftl::TaskRunner>& UI();
+  static const ftl::RefPtr<ftl::TaskRunner>& IO();
+
+  static void Set(const Threads& settings);
+
+ private:
+  static const Threads& Get();
+
+  ftl::RefPtr<ftl::TaskRunner> gpu_;
+  ftl::RefPtr<ftl::TaskRunner> ui_;
+  ftl::RefPtr<ftl::TaskRunner> io_;
+};
+
+}  // namespace blink
+
+#endif  // FLUTTER_COMMON_THREADS_H_

lib/jni/BUILD.gn

@@ -20,6 +20,6 @@ source_set("jni") {
 
   deps = [
     "//base",
-    "//flutter/tonic",
+    "//lib/tonic",
   ]
 }

lib/ui/BUILD.gn

@@ -41,10 +41,10 @@ source_set("ui") {
   ]
 
   deps = [
+    "//flutter/common",
     "//flutter/flow",
     "//flutter/glue",
     "//flutter/skia",
-    "//flutter/tonic",
     "//lib/tonic",
     "//lib/tonic/mojo",
   ]

lib/ui/painting/image_decoding.cc

@@ -4,15 +4,15 @@
 
 #include "flutter/lib/ui/painting/image_decoding.h"
 
+#include "flutter/common/threads.h"
 #include "flutter/flow/texture_image.h"
 #include "flutter/glue/drain_data_pipe_job.h"
 #include "flutter/glue/movable_wrapper.h"
 #include "flutter/glue/trace_event.h"
 #include "flutter/lib/ui/painting/image.h"
 #include "flutter/lib/ui/painting/resource_context.h"
-#include "flutter/tonic/dart_state.h"
-#include "lib/ftl/tasks/task_runner.h"
 #include "lib/tonic/dart_persistent_value.h"
+#include "lib/tonic/dart_state.h"
 #include "lib/tonic/logging/dart_invoke.h"
 #include "lib/tonic/mojo/mojo_converter.h"
 #include "lib/tonic/typed_data/uint8_list.h"
@@ -73,11 +73,10 @@ void InvokeImageCallback(sk_sp<SkImage> image,
 }
 
 void DecodeImageAndInvokeImageCallback(
-    ftl::RefPtr<ftl::TaskRunner> task_runner,
     glue::MovableWrapper<std::unique_ptr<DartPersistentValue>> callback,
     std::vector<char> buffer) {
   sk_sp<SkImage> image = DecodeImage(std::move(buffer));
-  task_runner->PostTask([callback, image]() mutable {
+  Threads::UI()->PostTask([callback, image]() mutable {
     InvokeImageCallback(image, callback.Unwrap());
   });
 }
@@ -99,23 +98,17 @@ void DecodeImageFromDataPipe(Dart_NativeArguments args) {
     return;
   }
 
-  DartState* dart_state = DartState::Current();
-  ftl::RefPtr<ftl::TaskRunner> task_runner = dart_state->ui_task_runner();
-
   auto callback = glue::WrapMovable(std::unique_ptr<DartPersistentValue>(
-      new DartPersistentValue(dart_state, callback_handle)));
-
-  dart_state->io_task_runner()->PostTask(
-      [task_runner, callback, consumer]() mutable {
-        glue::DrainDataPipeJob* job = nullptr;
-        job = new glue::DrainDataPipeJob(
-            consumer.Unwrap(),
-            [task_runner, callback, job](std::vector<char> buffer) {
-              delete job;
-              DecodeImageAndInvokeImageCallback(task_runner, callback,
-                                                std::move(buffer));
-            });
-      });
+      new DartPersistentValue(tonic::DartState::Current(), callback_handle)));
+
+  Threads::IO()->PostTask([callback, consumer]() mutable {
+    glue::DrainDataPipeJob* job = nullptr;
+    job = new glue::DrainDataPipeJob(
+        consumer.Unwrap(), [callback, job](std::vector<char> buffer) {
+          delete job;
+          DecodeImageAndInvokeImageCallback(callback, std::move(buffer));
+        });
+  });
 }
 
 void DecodeImageFromList(Dart_NativeArguments args) {
@@ -134,21 +127,16 @@ void DecodeImageFromList(Dart_NativeArguments args) {
     return;
   }
 
-  DartState* dart_state = DartState::Current();
-  ftl::RefPtr<ftl::TaskRunner> task_runner = dart_state->ui_task_runner();
-
   auto callback = glue::WrapMovable(std::unique_ptr<DartPersistentValue>(
-      new DartPersistentValue(dart_state, callback_handle)));
+      new DartPersistentValue(tonic::DartState::Current(), callback_handle)));
 
   const char* bytes = reinterpret_cast<const char*>(list.data());
   auto buffer = glue::WrapMovable(std::unique_ptr<std::vector<char>>(
       new std::vector<char>(bytes, bytes + list.num_elements())));
 
-  dart_state->io_task_runner()->PostTask(
-      [task_runner, callback, buffer]() mutable {
-        DecodeImageAndInvokeImageCallback(task_runner, callback,
-                                          std::move(*buffer.Unwrap()));
-      });
+  Threads::IO()->PostTask([callback, buffer]() mutable {
+    DecodeImageAndInvokeImageCallback(callback, std::move(*buffer.Unwrap()));
+  });
 }
 
 }  // namespace

sky/engine/bindings/BUILD.gn

@@ -24,7 +24,6 @@ source_set("bindings") {
     "//dart/runtime/bin:embedded_dart_io",
     "//flutter/assets",
     "//flutter/lib/ui",
-    "//flutter/tonic",
     "//lib/tonic",
     "//mojo/public/c/system",
     "//mojo/public/cpp/application",

sky/engine/bindings/dart_runtime_hooks.cc

@@ -11,17 +11,17 @@
 #include "dart/runtime/bin/embedded_dart_io.h"
 #include "dart/runtime/include/dart_api.h"
 #include "dart/runtime/include/dart_tools_api.h"
-#include "lib/tonic/dart_library_natives.h"
-#include "flutter/tonic/dart_state.h"
+#include "flutter/sky/engine/core/script/ui_dart_state.h"
+#include "flutter/sky/engine/wtf/text/WTFString.h"
 #include "lib/ftl/logging.h"
 #include "lib/tonic/converter/dart_converter.h"
+#include "lib/tonic/dart_library_natives.h"
 #include "lib/tonic/dart_microtask_queue.h"
+#include "lib/tonic/dart_state.h"
 #include "lib/tonic/logging/dart_error.h"
 #include "lib/tonic/logging/dart_invoke.h"
 #include "lib/tonic/scopes/dart_api_scope.h"
 #include "lib/tonic/scopes/dart_isolate_scope.h"
-#include "flutter/sky/engine/core/script/ui_dart_state.h"
-#include "flutter/sky/engine/wtf/text/WTFString.h"
 
 #if defined(OS_ANDROID)
 #include <android/log.h>

sky/engine/bindings/flutter_dart_state.h

@@ -8,9 +8,9 @@
 #include <string>
 
 #include "dart/runtime/include/dart_api.h"
-#include "flutter/tonic/dart_state.h"
 #include "lib/ftl/build_config.h"
 #include "lib/tonic/dart_persistent_value.h"
+#include "lib/tonic/dart_state.h"
 
 namespace blink {
 
@@ -25,7 +25,7 @@ class IsolateClient {
   virtual ~IsolateClient();
 };
 
-class FlutterDartState : public DartState {
+class FlutterDartState : public tonic::DartState {
  public:
   FlutterDartState* CreateForChildIsolate();
   ~FlutterDartState() override;
@@ -37,9 +37,7 @@ class FlutterDartState : public DartState {
 
   static FlutterDartState* Current();
 
-  Dart_Port main_port() const {
-    return main_port_;
-  }
+  Dart_Port main_port() const { return main_port_; }
 
   void set_mojo_services(std::unique_ptr<MojoServices> mojo_services);
   MojoServices* mojo_services();

sky/engine/bindings/mojo_services.cc

@@ -4,13 +4,15 @@
 
 #include "flutter/sky/engine/bindings/mojo_services.h"
 
+#include "flutter/sky/engine/bindings/flutter_dart_state.h"
 #include "lib/tonic/converter/dart_converter.h"
-#include "lib/tonic/logging/dart_error.h"
 #include "lib/tonic/dart_library_natives.h"
-#include "flutter/tonic/dart_state.h"
+#include "lib/tonic/dart_state.h"
+#include "lib/tonic/logging/dart_error.h"
 #include "mojo/public/cpp/application/connect.h"
 #include "mojo/public/cpp/bindings/array.h"
-#include "flutter/sky/engine/bindings/flutter_dart_state.h"
+
+using tonic::DartState;
 
 namespace blink {
 namespace {

sky/engine/core/BUILD.gn

@@ -10,11 +10,11 @@ visibility = [ "//flutter/sky/engine/*", "//flutter/sky/shell/*" ]
 source_set("libraries") {
   public_deps = [
     "//base",
+    "//flutter/common",
     "//flutter/flow",
     "//flutter/glue",
     "//flutter/lib/io",
     "//flutter/lib/ui",
-    "//flutter/tonic",
     "//lib/ftl",
     "//lib/tonic",
     "//lib/tonic/debugger",

sky/engine/core/script/dart_controller.cc

@@ -7,6 +7,8 @@
 #include <utility>
 
 #include "dart/runtime/include/dart_tools_api.h"
+#include "flutter/common/settings.h"
+#include "flutter/common/threads.h"
 #include "flutter/glue/trace_event.h"
 #include "flutter/lib/io/dart_io.h"
 #include "flutter/sky/engine/bindings/dart_mojo_internal.h"
@@ -16,13 +18,12 @@
 #include "flutter/sky/engine/core/script/dart_service_isolate.h"
 #include "flutter/sky/engine/core/script/ui_dart_state.h"
 #include "flutter/sky/engine/public/platform/Platform.h"
-#include "flutter/sky/engine/public/platform/sky_settings.h"
 #include "flutter/sky/engine/wtf/MakeUnique.h"
-#include "flutter/tonic/dart_state.h"
 #include "lib/ftl/files/directory.h"
 #include "lib/ftl/files/path.h"
 #include "lib/tonic/dart_class_library.h"
 #include "lib/tonic/dart_message_handler.h"
+#include "lib/tonic/dart_state.h"
 #include "lib/tonic/dart_wrappable.h"
 #include "lib/tonic/debugger/dart_debugger.h"
 #include "lib/tonic/file_loader/file_loader.h"
@@ -139,14 +140,13 @@ void DartController::CreateIsolateFor(std::unique_ptr<UIDartState> state) {
   Dart_Isolate isolate = Dart_CreateIsolate(
       state->url().c_str(), "main",
       reinterpret_cast<uint8_t*>(DART_SYMBOL(kDartIsolateSnapshotBuffer)),
-      nullptr, static_cast<DartState*>(state.get()), &error);
+      nullptr, static_cast<tonic::DartState*>(state.get()), &error);
   FTL_CHECK(isolate) << error;
   ui_dart_state_ = state.release();
   FTL_DCHECK(Platform::current());
-  dart_state()->message_handler().Initialize(
-      ftl::RefPtr<ftl::TaskRunner>(Platform::current()->GetUITaskRunner()));
+  dart_state()->message_handler().Initialize(blink::Threads::UI());
 
-  Dart_SetShouldPauseOnStart(SkySettings::Get().start_paused);
+  Dart_SetShouldPauseOnStart(Settings::Get().start_paused);
 
   ui_dart_state_->SetIsolate(isolate);
   FTL_CHECK(!LogIfError(

sky/engine/core/script/dart_init.cc

@@ -15,6 +15,7 @@
 #include "dart/runtime/bin/embedded_dart_io.h"
 #include "dart/runtime/include/dart_mirrors_api.h"
 #include "flutter/assets/zip_asset_store.h"
+#include "flutter/common/settings.h"
 #include "flutter/glue/trace_event.h"
 #include "flutter/lib/io/dart_io.h"
 #include "flutter/sky/engine/bindings/dart_mojo_internal.h"
@@ -23,14 +24,13 @@
 #include "flutter/sky/engine/core/script/dart_service_isolate.h"
 #include "flutter/sky/engine/core/script/ui_dart_state.h"
 #include "flutter/sky/engine/core/start_up.h"
-#include "flutter/sky/engine/public/platform/sky_settings.h"
 #include "flutter/sky/engine/wtf/MakeUnique.h"
-#include "flutter/tonic/dart_state.h"
 #include "lib/ftl/files/eintr_wrapper.h"
 #include "lib/ftl/files/unique_fd.h"
 #include "lib/ftl/logging.h"
 #include "lib/ftl/time/time_delta.h"
 #include "lib/tonic/dart_class_library.h"
+#include "lib/tonic/dart_state.h"
 #include "lib/tonic/dart_wrappable.h"
 #include "lib/tonic/debugger/dart_debugger.h"
 #include "lib/tonic/logging/dart_error.h"
@@ -120,7 +120,7 @@ RegisterNativeServiceProtocolExtensionHook
     g_register_native_service_protocol_extensions_hook = nullptr;
 
 void IsolateShutdownCallback(void* callback_data) {
-  DartState* dart_state = static_cast<DartState*>(callback_data);
+  tonic::DartState* dart_state = static_cast<tonic::DartState*>(callback_data);
   delete dart_state;
 }
 
@@ -175,7 +175,7 @@ Dart_Isolate ServiceIsolateCreateCallback(const char* script_uri,
 
 Dart_Isolate ServiceIsolateCreateCallback(const char* script_uri,
                                           char** error) {
-  DartState* dart_state = new DartState();
+  tonic::DartState* dart_state = new tonic::DartState();
   Dart_Isolate isolate = Dart_CreateIsolate(
       script_uri, "main",
       reinterpret_cast<const uint8_t*>(DART_SYMBOL(kDartIsolateSnapshotBuffer)),
@@ -191,7 +191,7 @@ Dart_Isolate ServiceIsolateCreateCallback(const char* script_uri,
     DartUI::InitForIsolate();
     DartMojoInternal::InitForIsolate();
     DartRuntimeHooks::Install(DartRuntimeHooks::SecondaryIsolate, "");
-    const SkySettings& settings = SkySettings::Get();
+    const Settings& settings = Settings::Get();
     if (settings.enable_observatory) {
       std::string ip = "127.0.0.1";
       const intptr_t port = settings.observatory_port;
@@ -402,7 +402,7 @@ void* _DartSymbolLookup(const char* symbol_name) {
       return symbol_asset.mapping;
     }
 
-    const std::string& aot_snapshot_path = SkySettings::Get().aot_snapshot_path;
+    const std::string& aot_snapshot_path = Settings::Get().aot_snapshot_path;
     FTL_CHECK(!aot_snapshot_path.empty());
 
     std::string asset_path = aot_snapshot_path + "/" + symbol_asset.file_name;
@@ -506,14 +506,14 @@ static bool ShouldEnableCheckedMode() {
 #if ENABLE(DART_STRICT)
   return true;
 #else
-  return SkySettings::Get().enable_dart_checked_mode;
+  return Settings::Get().enable_dart_checked_mode;
 #endif
 }
 
 void InitDartVM() {
   TRACE_EVENT0("flutter", __func__);
 
-  const SkySettings& settings = SkySettings::Get();
+  const Settings& settings = Settings::Get();
 
   {
     TRACE_EVENT0("flutter", "dart::bin::BootstrapDartIo");

sky/engine/core/script/ui_dart_state.cc

@@ -12,12 +12,7 @@ namespace blink {
 UIDartState::UIDartState(IsolateClient* isolate_client,
                          const std::string& url,
                          std::unique_ptr<Window> window)
-    : FlutterDartState(isolate_client, url), window_(std::move(window)) {
-  ui_task_runner_ =
-      ftl::RefPtr<ftl::TaskRunner>(Platform::current()->GetUITaskRunner());
-  io_task_runner_ =
-      ftl::RefPtr<ftl::TaskRunner>(Platform::current()->GetIOTaskRunner());
-}
+    : FlutterDartState(isolate_client, url), window_(std::move(window)) {}
 
 UIDartState::~UIDartState() {}
 

sky/engine/core/text/Paragraph.cpp

@@ -4,11 +4,7 @@
 
 #include "flutter/sky/engine/core/text/ParagraphBuilder.h"
 
-#include "lib/tonic/dart_args.h"
-#include "lib/tonic/dart_binding_macros.h"
-#include "lib/tonic/dart_library_natives.h"
-#include "lib/ftl/tasks/task_runner.h"
-#include "lib/tonic/converter/dart_converter.h"
+#include "flutter/common/threads.h"
 #include "flutter/sky/engine/core/rendering/PaintInfo.h"
 #include "flutter/sky/engine/core/rendering/RenderText.h"
 #include "flutter/sky/engine/core/rendering/style/RenderStyle.h"
@@ -16,6 +12,11 @@
 #include "flutter/sky/engine/platform/graphics/GraphicsContext.h"
 #include "flutter/sky/engine/platform/text/TextBoundaries.h"
 #include "flutter/sky/engine/public/platform/Platform.h"
+#include "lib/ftl/tasks/task_runner.h"
+#include "lib/tonic/converter/dart_converter.h"
+#include "lib/tonic/dart_args.h"
+#include "lib/tonic/dart_binding_macros.h"
+#include "lib/tonic/dart_library_natives.h"
 
 using tonic::ToDart;
 
@@ -43,7 +44,7 @@ Paragraph::Paragraph(PassOwnPtr<RenderView> renderView)
 
 Paragraph::~Paragraph() {
   PassOwnPtr<RenderView> renderView = m_renderView.release();
-  Platform::current()->GetUITaskRunner()->PostTask(
+  Threads::UI()->PostTask(
       [renderView]() { /* renderView's destructor runs. */ });
 }
 

sky/engine/core/text/ParagraphBuilder.cpp

@@ -4,11 +4,7 @@
 
 #include "flutter/sky/engine/core/text/ParagraphBuilder.h"
 
-#include "lib/tonic/dart_args.h"
-#include "lib/tonic/dart_binding_macros.h"
-#include "lib/tonic/dart_library_natives.h"
-#include "lib/ftl/tasks/task_runner.h"
-#include "lib/tonic/converter/dart_converter.h"
+#include "flutter/common/threads.h"
 #include "flutter/sky/engine/core/rendering/RenderInline.h"
 #include "flutter/sky/engine/core/rendering/RenderParagraph.h"
 #include "flutter/sky/engine/core/rendering/RenderText.h"
@@ -16,6 +12,11 @@
 #include "flutter/sky/engine/core/script/ui_dart_state.h"
 #include "flutter/sky/engine/platform/text/LocaleToScriptMapping.h"
 #include "flutter/sky/engine/public/platform/Platform.h"
+#include "lib/ftl/tasks/task_runner.h"
+#include "lib/tonic/converter/dart_converter.h"
+#include "lib/tonic/dart_args.h"
+#include "lib/tonic/dart_binding_macros.h"
+#include "lib/tonic/dart_library_natives.h"
 
 namespace blink {
 namespace {
@@ -137,7 +138,7 @@ ParagraphBuilder::ParagraphBuilder() {
 
 ParagraphBuilder::~ParagraphBuilder() {
   PassOwnPtr<RenderView> renderView = m_renderView.release();
-  Platform::current()->GetUITaskRunner()->PostTask(
+  Threads::UI()->PostTask(
       [renderView]() { /* renderView's destructor runs. */ });
 }
 

sky/engine/core/window/window.cc

@@ -11,6 +11,7 @@
 #include "flutter/sky/engine/core/script/ui_dart_state.h"
 
 using tonic::DartInvokeField;
+using tonic::DartState;
 using tonic::StdStringToDart;
 using tonic::ToDart;
 

sky/engine/platform/BUILD.gn

@@ -39,7 +39,6 @@ source_set("platform") {
     "animation/TimingFunction.h",
     "animation/UnitBezier.h",
     "exported/Platform.cpp",
-    "exported/sky_settings.cc",
     "exported/WebCommon.cpp",
     "fonts/AlternateFontFamily.h",
     "fonts/Character.cpp",

sky/engine/platform/SharedBuffer.cpp

@@ -26,9 +26,10 @@
 
 #include "flutter/sky/engine/platform/SharedBuffer.h"
 
+#include "flutter/common/threads.h"
 #include "flutter/sky/engine/public/platform/Platform.h"
-#include "flutter/sky/engine/wtf/unicode/UTF8.h"
 #include "flutter/sky/engine/wtf/unicode/Unicode.h"
+#include "flutter/sky/engine/wtf/unicode/UTF8.h"
 
 #undef SHARED_BUFFER_STATS
 
@@ -116,7 +117,7 @@ static void didCreateSharedBuffer(SharedBuffer* buffer) {
   MutexLocker locker(statsMutex());
   liveBuffers().add(buffer);
 
-  Platform::current()->GetUITaskRunner()->PostTask(printStats);
+  Threads::UI()->PostTask(printStats);
 }
 
 static void willDestroySharedBuffer(SharedBuffer* buffer) {

sky/engine/public/platform/Platform.h

@@ -35,10 +35,6 @@
 
 #include "flutter/sky/engine/public/platform/WebCommon.h"
 
-namespace ftl {
-class TaskRunner;
-}
-
 namespace blink {
 class WebDiscardableMemory;
 
@@ -65,9 +61,6 @@ class Platform {
   // Returns a value such as "en-US".
   virtual std::string defaultLocale() { return std::string(); }
 
-  virtual ftl::TaskRunner* GetUITaskRunner() { return nullptr; }
-  virtual ftl::TaskRunner* GetIOTaskRunner() { return nullptr; }
-
  protected:
   virtual ~Platform() {}
 };

sky/engine/public/sky/sky_view.cc

@@ -12,6 +12,8 @@
 #include "flutter/sky/engine/public/sky/sky_view_client.h"
 #include "flutter/sky/engine/wtf/MakeUnique.h"
 
+using tonic::DartState;
+
 namespace blink {
 
 std::unique_ptr<SkyView> SkyView::Create(SkyViewClient* client) {

sky/shell/BUILD.gn

@@ -51,10 +51,10 @@ source_set("common") {
     "//base",
     "//build/config/sanitizers:deps",
     "//dart/runtime:libdart",
+    "//flutter/common",
     "//flutter/flow",
     "//flutter/assets",
     "//flutter/lib/ui",
-    "//flutter/tonic",
     "//flutter/glue",
     "//lib/ftl",
     "//lib/tonic",

sky/shell/diagnostic/diagnostic_server.cc

@@ -6,16 +6,17 @@
 
 #include "dart/runtime/include/dart_api.h"
 #include "dart/runtime/include/dart_native_api.h"
+#include "flutter/common/threads.h"
 #include "flutter/flow/compositor_context.h"
-#include "lib/ftl/logging.h"
-#include "lib/tonic/dart_binding_macros.h"
-#include "lib/tonic/dart_library_natives.h"
-#include "lib/tonic/logging/dart_invoke.h"
 #include "flutter/sky/engine/core/script/embedder_resources.h"
 #include "flutter/sky/shell/gpu/picture_serializer.h"
 #include "flutter/sky/shell/rasterizer.h"
 #include "flutter/sky/shell/shell.h"
 #include "flutter/sky/shell/ui/engine.h"
+#include "lib/ftl/logging.h"
+#include "lib/tonic/dart_binding_macros.h"
+#include "lib/tonic/dart_library_natives.h"
+#include "lib/tonic/logging/dart_invoke.h"
 #include "third_party/skia/include/core/SkStream.h"
 
 namespace mojo {
@@ -98,8 +99,7 @@ void DiagnosticServer::HandleSkiaPictureRequest(Dart_Handle send_port) {
   Dart_Port port_id;
   FTL_CHECK(!LogIfError(Dart_SendPortGetId(send_port, &port_id)));
 
-  Shell::Shared().gpu_ftl_task_runner()->PostTask(
-      [port_id]() { SkiaPictureTask(port_id); });
+  blink::Threads::Gpu()->PostTask([port_id]() { SkiaPictureTask(port_id); });
 }
 
 void DiagnosticServer::SkiaPictureTask(Dart_Port port_id) {

sky/shell/platform/mojo/BUILD.gn

@@ -23,7 +23,14 @@ mojo_native_application("mojo") {
   ]
 
   deps = [
-    "//flutter/tonic",
+    "//flutter/common",
+    "//flutter/services/icu",
+    "//flutter/services/raw_keyboard:interfaces",
+    "//flutter/skia",
+    "//flutter/sky/engine/public/sky",
+    "//flutter/sky/engine/web",
+    "//flutter/sky/shell:common",
+    "//flutter/sky/shell:gpu_mojo",
     "//mojo/application",
     "//mojo/common:tracing_impl",
     "//mojo/common",
@@ -36,13 +43,6 @@ mojo_native_application("mojo") {
     "//mojo/services/input_events/interfaces",
     "//mojo/services/ui/input/interfaces",
     "//mojo/services/ui/views/interfaces",
-    "//flutter/services/icu",
-    "//flutter/skia",
-    "//flutter/sky/engine/public/sky",
-    "//flutter/sky/engine/web",
-    "//flutter/services/raw_keyboard:interfaces",
-    "//flutter/sky/shell:common",
-    "//flutter/sky/shell:gpu_mojo",
     "//third_party/icu",
   ]
 

sky/shell/platform/mojo/main_mojo.cc

@@ -5,6 +5,10 @@
 #include "base/files/file_path.h"
 #include "base/message_loop/message_loop.h"
 #include "base/threading/thread.h"
+#include "flutter/common/settings.h"
+#include "flutter/services/icu/icu.h"
+#include "flutter/sky/shell/platform/mojo/content_handler_impl.h"
+#include "flutter/sky/shell/shell.h"
 #include "mojo/common/tracing_impl.h"
 #include "mojo/environment/scoped_chromium_init.h"
 #include "mojo/public/c/system/main.h"
@@ -13,10 +17,6 @@
 #include "mojo/public/cpp/application/run_application.h"
 #include "mojo/public/cpp/application/service_provider_impl.h"
 #include "mojo/services/content_handler/interfaces/content_handler.mojom.h"
-#include "flutter/services/icu/icu.h"
-#include "flutter/sky/engine/public/platform/sky_settings.h"
-#include "flutter/sky/shell/platform/mojo/content_handler_impl.h"
-#include "flutter/sky/shell/shell.h"
 
 namespace sky {
 namespace shell {
@@ -30,7 +30,7 @@ const char kPauseIsolatesOnStart[] = "--pause-isolates-on-start";
 class MojoApp : public mojo::ApplicationImplBase {
  public:
   MojoApp() {}
-  ~MojoApp() override { }
+  ~MojoApp() override {}
 
  private:
   // Overridden from ApplicationDelegate:
@@ -41,11 +41,11 @@ class MojoApp : public mojo::ApplicationImplBase {
     mojo::icu::Initialize(application_connector.get());
     tracing_.Initialize(shell(), &args());
 
-    blink::SkySettings settings;
+    blink::Settings settings;
     settings.enable_observatory = true;
     settings.enable_dart_checked_mode = HasArg(kEnableCheckedMode);
     settings.start_paused = HasArg(kPauseIsolatesOnStart);
-    blink::SkySettings::Set(settings);
+    blink::Settings::Set(settings);
 
     Shell::Init();
   }
@@ -53,10 +53,10 @@ class MojoApp : public mojo::ApplicationImplBase {
   bool OnAcceptConnection(
       mojo::ServiceProviderImpl* service_provider_impl) override {
     service_provider_impl->AddService<mojo::ContentHandler>(
-      [](const mojo::ConnectionContext& connection_context,
-         mojo::InterfaceRequest<mojo::ContentHandler> request) {
-        new ContentHandlerImpl(request.Pass());
-      });
+        [](const mojo::ConnectionContext& connection_context,
+           mojo::InterfaceRequest<mojo::ContentHandler> request) {
+          new ContentHandlerImpl(request.Pass());
+        });
     return true;
   }
 

sky/shell/platform_view.cc

@@ -6,8 +6,9 @@
 
 #include <utility>
 
-#include "flutter/lib/ui/painting/resource_context.h"
+#include "flutter/common/threads.h"
 #include "flutter/glue/movable_wrapper.h"
+#include "flutter/lib/ui/painting/resource_context.h"
 #include "flutter/sky/shell/rasterizer.h"
 #include "third_party/skia/include/gpu/gl/GrGLInterface.h"
 
@@ -20,19 +21,15 @@ PlatformView::Config::~Config() = default;
 
 PlatformView::PlatformView()
     : rasterizer_(Rasterizer::Create()), size_(SkISize::Make(0, 0)) {
-  Shell& shell = Shell::Shared();
-
   // Create the engine for this platform view.
   Engine::Config engine_config;
-  engine_config.gpu_task_runner =
-      ftl::RefPtr<ftl::TaskRunner>(shell.gpu_ftl_task_runner());
 
   ftl::WeakPtr<Rasterizer> rasterizer_impl =
       rasterizer_->GetWeakRasterizerPtr();
   rasterizer::RasterizerPtr rasterizer;
   auto request = glue::WrapMovable(mojo::GetProxy(&rasterizer));
 
-  shell.gpu_ftl_task_runner()->PostTask([rasterizer_impl, request]() mutable {
+  blink::Threads::Gpu()->PostTask([rasterizer_impl, request]() mutable {
     if (rasterizer_impl)
       rasterizer_impl->ConnectToRasterizer(request.Unwrap());
   });
@@ -40,34 +37,30 @@ PlatformView::PlatformView()
   engine_.reset(new Engine(engine_config, rasterizer.Pass()));
 
   // Setup the platform config.
-  config_.ui_task_runner =
-      ftl::RefPtr<ftl::TaskRunner>(shell.ui_ftl_task_runner());
   config_.ui_delegate = engine_->GetWeakPtr();
   config_.rasterizer = rasterizer_.get();
 }
 
 PlatformView::~PlatformView() {
-  Shell& shell = Shell::Shared();
-
-  shell.ui_ftl_task_runner()->PostTask(
+  blink::Threads::UI()->PostTask(
       []() { Shell::Shared().PurgePlatformViews(); });
 
   Rasterizer* rasterizer = rasterizer_.release();
-  shell.gpu_ftl_task_runner()->PostTask([rasterizer]() { delete rasterizer; });
+  blink::Threads::Gpu()->PostTask([rasterizer]() { delete rasterizer; });
 
   Engine* engine = engine_.release();
-  shell.ui_ftl_task_runner()->PostTask([engine]() { delete engine; });
+  blink::Threads::UI()->PostTask([engine]() { delete engine; });
 }
 
 void PlatformView::ConnectToEngine(mojo::InterfaceRequest<SkyEngine> request) {
   ftl::WeakPtr<UIDelegate> ui_delegate = config_.ui_delegate;
   auto wrapped_request = glue::WrapMovable(std::move(request));
-  config_.ui_task_runner->PostTask([ui_delegate, wrapped_request]() mutable {
+  blink::Threads::UI()->PostTask([ui_delegate, wrapped_request]() mutable {
     if (ui_delegate)
       ui_delegate->ConnectToEngine(wrapped_request.Unwrap());
   });
   ftl::WeakPtr<PlatformView> view = GetWeakViewPtr();
-  config_.ui_task_runner->PostTask(
+  blink::Threads::UI()->PostTask(
       [view]() { Shell::Shared().AddPlatformView(view); });
 }
 
@@ -89,7 +82,7 @@ void PlatformView::NotifyCreated(ftl::Closure rasterizer_continuation) {
   };
 
   auto delegate = config_.ui_delegate;
-  config_.ui_task_runner->PostTask([delegate, delegate_continuation]() {
+  blink::Threads::UI()->PostTask([delegate, delegate_continuation]() {
     if (delegate)
       delegate->OnOutputSurfaceCreated(delegate_continuation);
     // TODO(abarth): We should signal the latch if the delegate is gone.
@@ -112,7 +105,7 @@ void PlatformView::NotifyDestroyed() {
     // TODO(abarth): We should signal the latch if the rasterizer is gone.
   };
 
-  config_.ui_task_runner->PostTask([delegate, delegate_continuation]() {
+  blink::Threads::UI()->PostTask([delegate, delegate_continuation]() {
     if (delegate)
       delegate->OnOutputSurfaceDestroyed(delegate_continuation);
     // TODO(abarth): We should signal the latch if the delegate is gone.
@@ -132,7 +125,7 @@ void PlatformView::Resize(const SkISize& size) {
 void PlatformView::SetupResourceContextOnIOThread() {
   ftl::AutoResetWaitableEvent latch;
 
-  Shell::Shared().io_ftl_task_runner()->PostTask(
+  blink::Threads::IO()->PostTask(
       [this, &latch]() { SetupResourceContextOnIOThreadPerform(&latch); });
 
   latch.Wait();

sky/shell/platform_view.h

@@ -30,7 +30,6 @@ class PlatformView {
 
     ftl::WeakPtr<UIDelegate> ui_delegate;
     Rasterizer* rasterizer;
-    ftl::RefPtr<ftl::TaskRunner> ui_task_runner;
   };
 
   struct SurfaceConfig {

sky/shell/shell.cc

@@ -18,16 +18,17 @@
 #include "base/single_thread_task_runner.h"
 #include "base/trace_event/trace_event.h"
 #include "dart/runtime/include/dart_tools_api.h"
+#include "flutter/common/settings.h"
+#include "flutter/common/threads.h"
 #include "flutter/glue/task_runner_adaptor.h"
-#include "lib/ftl/files/unique_fd.h"
-#include "mojo/message_pump/message_pump_mojo.h"
 #include "flutter/skia/ext/event_tracer_impl.h"
 #include "flutter/sky/engine/core/script/dart_init.h"
-#include "flutter/sky/engine/public/platform/sky_settings.h"
 #include "flutter/sky/shell/diagnostic/diagnostic_server.h"
 #include "flutter/sky/shell/platform_view_service_protocol.h"
 #include "flutter/sky/shell/switches.h"
 #include "flutter/sky/shell/ui/engine.h"
+#include "lib/ftl/files/unique_fd.h"
+#include "mojo/message_pump/message_pump_mojo.h"
 
 namespace sky {
 namespace shell {
@@ -70,7 +71,7 @@ base::LazyInstance<NonDiscardableMemoryAllocator> g_discardable;
 
 void ServiceIsolateHook(bool running_precompiled) {
   if (!running_precompiled) {
-    const blink::SkySettings& settings = blink::SkySettings::Get();
+    const blink::Settings& settings = blink::Settings::Get();
     if (settings.enable_observatory)
       DiagnosticServer::Start();
   }
@@ -86,20 +87,23 @@ Shell::Shell() {
 
   gpu_thread_.reset(new base::Thread("gpu_thread"));
   gpu_thread_->StartWithOptions(options);
-  gpu_ftl_task_runner_ = ftl::MakeRefCounted<glue::TaskRunnerAdaptor>(
-      gpu_thread_->message_loop()->task_runner());
-  gpu_ftl_task_runner_->PostTask([this]() { InitGpuThread(); });
 
   ui_thread_.reset(new base::Thread("ui_thread"));
   ui_thread_->StartWithOptions(options);
-  ui_ftl_task_runner_ = ftl::MakeRefCounted<glue::TaskRunnerAdaptor>(
-      ui_thread_->message_loop()->task_runner());
-  ui_ftl_task_runner_->PostTask([this]() { InitUIThread(); });
 
   io_thread_.reset(new base::Thread("io_thread"));
   io_thread_->StartWithOptions(options);
-  io_ftl_task_runner_ = ftl::MakeRefCounted<glue::TaskRunnerAdaptor>(
-      io_thread_->message_loop()->task_runner());
+
+  blink::Threads threads(ftl::MakeRefCounted<glue::TaskRunnerAdaptor>(
+                             gpu_thread_->message_loop()->task_runner()),
+                         ftl::MakeRefCounted<glue::TaskRunnerAdaptor>(
+                             ui_thread_->message_loop()->task_runner()),
+                         ftl::MakeRefCounted<glue::TaskRunnerAdaptor>(
+                             io_thread_->message_loop()->task_runner()));
+  blink::Threads::Set(threads);
+
+  blink::Threads::Gpu()->PostTask([this]() { InitGpuThread(); });
+  blink::Threads::UI()->PostTask([this]() { InitUIThread(); });
 
   blink::SetServiceIsolateHook(ServiceIsolateHook);
   blink::SetRegisterNativeServiceProtocolExtensionHook(
@@ -126,7 +130,7 @@ void Shell::InitStandalone(std::string icu_data_path) {
 
   base::CommandLine& command_line = *base::CommandLine::ForCurrentProcess();
 
-  blink::SkySettings settings;
+  blink::Settings settings;
   // Enable Observatory
   settings.enable_observatory =
       !command_line.HasSwitch(switches::kNonInteractive);
@@ -163,7 +167,7 @@ void Shell::InitStandalone(std::string icu_data_path) {
       settings.dart_flags.push_back(*it);
   }
 
-  blink::SkySettings::Set(settings);
+  blink::Settings::Set(settings);
 
   Init();
 }
@@ -177,7 +181,7 @@ void Shell::Init() {
 
   FTL_DCHECK(!g_shell);
   g_shell = new Shell();
-  g_shell->ui_ftl_task_runner()->PostTask(Engine::Init);
+  blink::Threads::UI()->PostTask(Engine::Init);
 }
 
 Shell& Shell::Shared() {
@@ -238,7 +242,7 @@ void Shell::WaitForPlatformViewIds(
     std::vector<PlatformViewInfo>* platform_view_ids) {
   ftl::AutoResetWaitableEvent latch;
 
-  ui_ftl_task_runner()->PostTask([this, platform_view_ids, &latch]() {
+  blink::Threads::UI()->PostTask([this, platform_view_ids, &latch]() {
     WaitForPlatformViewsIdsUIThread(platform_view_ids, &latch);
   });
 
@@ -277,7 +281,7 @@ void Shell::RunInPlatformView(uintptr_t view_id,
   FTL_DCHECK(asset_directory);
   FTL_DCHECK(view_existed);
 
-  ui_ftl_task_runner()->PostTask([this, view_id, main_script, packages_file,
+  blink::Threads::UI()->PostTask([this, view_id, main_script, packages_file,
                                   asset_directory, view_existed,
                                   dart_isolate_id, &latch]() {
     RunInPlatformViewUIThread(view_id, main_script, packages_file,

sky/shell/shell.h

@@ -31,18 +31,6 @@ class Shell {
 
   static Shell& Shared();
 
-  ftl::TaskRunner* gpu_ftl_task_runner() const {
-    return gpu_ftl_task_runner_.get();
-  }
-
-  ftl::TaskRunner* ui_ftl_task_runner() const {
-    return ui_ftl_task_runner_.get();
-  }
-
-  ftl::TaskRunner* io_ftl_task_runner() const {
-    return io_ftl_task_runner_.get();
-  }
-
   TracingController& tracing_controller();
 
   // Maintain a list of rasterizers.
@@ -99,10 +87,6 @@ class Shell {
   std::unique_ptr<base::Thread> ui_thread_;
   std::unique_ptr<base::Thread> io_thread_;
 
-  ftl::RefPtr<ftl::TaskRunner> gpu_ftl_task_runner_;
-  ftl::RefPtr<ftl::TaskRunner> ui_ftl_task_runner_;
-  ftl::RefPtr<ftl::TaskRunner> io_ftl_task_runner_;
-
   std::unique_ptr<base::ThreadChecker> gpu_thread_checker_;
   std::unique_ptr<base::ThreadChecker> ui_thread_checker_;
 

sky/shell/tracing_controller.cc

@@ -6,10 +6,11 @@
 
 #include "base/trace_event/trace_event.h"
 #include "dart/runtime/include/dart_tools_api.h"
-#include "lib/ftl/logging.h"
+#include "flutter/common/threads.h"
 #include "flutter/sky/engine/core/script/dart_init.h"
 #include "flutter/sky/engine/wtf/MakeUnique.h"
 #include "flutter/sky/shell/shell.h"
+#include "lib/ftl/logging.h"
 
 #include <string>
 
@@ -144,12 +145,9 @@ static void BaseTraceEventCallback(base::TraceTicks timestamp,
 }
 
 static void AddTraceMetadata() {
-  Shell::Shared().gpu_ftl_task_runner()->PostTask(
-      []() { Dart_SetThreadName("gpu_thread"); });
-  Shell::Shared().ui_ftl_task_runner()->PostTask(
-      []() { Dart_SetThreadName("ui_thread"); });
-  Shell::Shared().io_ftl_task_runner()->PostTask(
-      []() { Dart_SetThreadName("io_thread"); });
+  blink::Threads::Gpu()->PostTask([]() { Dart_SetThreadName("gpu_thread"); });
+  blink::Threads::UI()->PostTask([]() { Dart_SetThreadName("ui_thread"); });
+  blink::Threads::IO()->PostTask([]() { Dart_SetThreadName("io_thread"); });
 }
 
 void TracingController::StartTracing() {

sky/shell/ui/engine.cc

@@ -10,10 +10,9 @@
 
 #include "flutter/assets/directory_asset_bundle.h"
 #include "flutter/assets/zip_asset_bundle.h"
+#include "flutter/common/threads.h"
 #include "flutter/glue/movable_wrapper.h"
 #include "flutter/glue/trace_event.h"
-#include "lib/ftl/files/path.h"
-#include "mojo/public/cpp/application/connect.h"
 #include "flutter/sky/engine/bindings/mojo_services.h"
 #include "flutter/sky/engine/core/script/dart_controller.h"
 #include "flutter/sky/engine/core/script/dart_init.h"
@@ -23,6 +22,8 @@
 #include "flutter/sky/shell/ui/animator.h"
 #include "flutter/sky/shell/ui/flutter_font_selector.h"
 #include "flutter/sky/shell/ui/platform_impl.h"
+#include "lib/ftl/files/path.h"
+#include "mojo/public/cpp/application/connect.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkPictureRecorder.h"
 
@@ -106,7 +107,7 @@ void Engine::ConnectToEngine(mojo::InterfaceRequest<SkyEngine> request) {
 }
 
 void Engine::OnOutputSurfaceCreated(const ftl::Closure& gpu_continuation) {
-  config_.gpu_task_runner->PostTask(gpu_continuation);
+  blink::Threads::Gpu()->PostTask(gpu_continuation);
   have_surface_ = true;
   StartAnimatorIfPossible();
   if (sky_view_)
@@ -116,7 +117,7 @@ void Engine::OnOutputSurfaceCreated(const ftl::Closure& gpu_continuation) {
 void Engine::OnOutputSurfaceDestroyed(const ftl::Closure& gpu_continuation) {
   have_surface_ = false;
   StopAnimator();
-  config_.gpu_task_runner->PostTask(gpu_continuation);
+  blink::Threads::Gpu()->PostTask(gpu_continuation);
 }
 
 void Engine::SetServices(ServicesDataPtr services) {
@@ -194,17 +195,14 @@ void Engine::RunFromSnapshotStream(
 }
 
 void Engine::ConfigureZipAssetBundle(const std::string& path) {
-  asset_store_ = ftl::MakeRefCounted<blink::ZipAssetStore>(
-      path, ftl::RefPtr<ftl::TaskRunner>(
-                blink::Platform::current()->GetIOTaskRunner()));
+  asset_store_ =
+      ftl::MakeRefCounted<blink::ZipAssetStore>(path, blink::Threads::IO());
   new blink::ZipAssetBundle(mojo::GetProxy(&root_bundle_), asset_store_);
 }
 
 void Engine::ConfigureDirectoryAssetBundle(const std::string& path) {
-  new blink::DirectoryAssetBundle(
-      mojo::GetProxy(&root_bundle_), path,
-      ftl::RefPtr<ftl::TaskRunner>(
-          blink::Platform::current()->GetIOTaskRunner()));
+  new blink::DirectoryAssetBundle(mojo::GetProxy(&root_bundle_), path,
+                                  blink::Threads::IO());
 }
 
 void Engine::ConfigureView(const std::string& script_uri) {
@@ -300,11 +298,10 @@ void Engine::DidCreateSecondaryIsolate(Dart_Isolate isolate) {
   mojo::ServiceProviderPtr services_from_embedder;
   auto request = glue::WrapMovable(mojo::GetProxy(&services_from_embedder));
   ftl::WeakPtr<Engine> engine = weak_factory_.GetWeakPtr();
-  blink::Platform::current()->GetUITaskRunner()->PostTask(
-      [engine, request]() mutable {
-        if (engine)
-          engine->BindToServiceProvider(request.Unwrap());
-      });
+  blink::Threads::UI()->PostTask([engine, request]() mutable {
+    if (engine)
+      engine->BindToServiceProvider(request.Unwrap());
+  });
   blink::MojoServices::Create(isolate, nullptr,
                               std::move(services_from_embedder), nullptr);
 }

sky/shell/ui/engine.h

@@ -14,7 +14,6 @@
 #include "flutter/sky/shell/ui_delegate.h"
 #include "lib/ftl/macros.h"
 #include "lib/ftl/memory/weak_ptr.h"
-#include "lib/ftl/tasks/task_runner.h"
 #include "mojo/public/cpp/application/service_provider_impl.h"
 #include "mojo/public/cpp/bindings/binding_set.h"
 #include "mojo/public/cpp/bindings/binding.h"
@@ -36,8 +35,6 @@ class Engine : public UIDelegate,
   struct Config {
     Config();
     ~Config();
-
-    ftl::RefPtr<ftl::TaskRunner> gpu_task_runner;
   };
 
   explicit Engine(const Config& config, rasterizer::RasterizerPtr rasterizer);

sky/shell/ui/platform_impl.cc

@@ -17,13 +17,5 @@ std::string PlatformImpl::defaultLocale() {
   return "en-US";
 }
 
-ftl::TaskRunner* PlatformImpl::GetUITaskRunner() {
-  return Shell::Shared().ui_ftl_task_runner();
-}
-
-ftl::TaskRunner* PlatformImpl::GetIOTaskRunner() {
-  return Shell::Shared().io_ftl_task_runner();
-}
-
 }  // namespace shell
 }  // namespace sky

sky/shell/ui/platform_impl.h

@@ -19,9 +19,6 @@ class PlatformImpl : public blink::Platform {
   // blink::Platform methods:
   std::string defaultLocale() override;
 
-  ftl::TaskRunner* GetUITaskRunner() override;
-  ftl::TaskRunner* GetIOTaskRunner() override;
-
  private:
   FTL_DISALLOW_COPY_AND_ASSIGN(PlatformImpl);
 };

tonic/dart_state.cc

-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "flutter/tonic/dart_state.h"
-
-namespace blink {
-
-DartState::DartState() {}
-
-DartState::~DartState() {}
-
-DartState* DartState::From(Dart_Isolate isolate) {
-  return static_cast<DartState*>(tonic::DartState::From(isolate));
-}
-
-DartState* DartState::Current() {
-  return static_cast<DartState*>(tonic::DartState::Current());
-}
-
-}  // namespace blink

tonic/dart_state.h

-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef FLUTTER_TONIC_DART_STATE_H_
-#define FLUTTER_TONIC_DART_STATE_H_
-
-#include <utility>
-
-#include "dart/runtime/include/dart_api.h"
-#include "lib/ftl/tasks/task_runner.h"
-#include "lib/tonic/dart_persistent_value.h"
-#include "lib/tonic/dart_state.h"
-#include "lib/tonic/scopes/dart_api_scope.h"
-#include "lib/tonic/scopes/dart_isolate_scope.h"
-
-namespace blink {
-
-class DartState : public tonic::DartState {
- public:
-  DartState();
-  virtual ~DartState();
-
-  static DartState* From(Dart_Isolate isolate);
-  static DartState* Current();
-
-  const ftl::RefPtr<ftl::TaskRunner>& ui_task_runner() {
-    return ui_task_runner_;
-  }
-  const ftl::RefPtr<ftl::TaskRunner>& io_task_runner() {
-    return io_task_runner_;
-  }
-
- protected:
-  ftl::RefPtr<ftl::TaskRunner> ui_task_runner_;
-  ftl::RefPtr<ftl::TaskRunner> io_task_runner_;
-
-  FTL_DISALLOW_COPY_AND_ASSIGN(DartState);
-};
-
-}  // namespace blink
-
-#endif  // FLUTTER_TONIC_DART_STATE_H_