Dont destroy the platform message loop on the Mac because the message pump is...

Dont destroy the platform message loop on the Mac because the message pump is still not collected when the embedder state goes away.

sky/shell/platform/mac/platform_mac.mm

@@ -14,6 +14,7 @@
 #include "base/logging.h"
 #include "base/mac/scoped_nsautorelease_pool.h"
 #include "base/message_loop/message_loop.h"
+#include "base/trace_event/trace_event.h"
 #include "mojo/edk/embedder/embedder.h"
 #include "mojo/edk/embedder/simple_platform_support.h"
 #include "sky/engine/wtf/MakeUnique.h"
@@ -22,7 +23,6 @@
 #include "sky/shell/tracing_controller.h"
 #include "sky/shell/ui_delegate.h"
 #include "ui/gl/gl_surface.h"
-#include "base/trace_event/trace_event.h"
 
 namespace sky {
 namespace shell {
@@ -49,6 +49,9 @@ static void RedirectIOConnectionsToSyslog() {
 class EmbedderState {
  public:
   EmbedderState(int argc, const char* argv[], std::string icu_data_path) {
+    CHECK([NSThread isMainThread])
+        << "Embedder initialization must occur on the main platform thread";
+
     RedirectIOConnectionsToSyslog();
 
     base::CommandLine::Init(argc, argv);
@@ -70,10 +73,12 @@ class EmbedderState {
     // marker that can be used as a reference for startup.
     TRACE_EVENT_INSTANT0("flutter", "main", TRACE_EVENT_SCOPE_PROCESS);
 
+    embedder_message_loop_ = WTF::MakeUnique<base::MessageLoopForUI>();
+
 #if TARGET_OS_IPHONE
     // One cannot start the message loop on the platform main thread. Instead,
     // we attach to the CFRunLoop
-    embedder_message_loop_.Attach();
+    embedder_message_loop_->Attach();
 #endif
 
     mojo::embedder::Init(mojo::embedder::CreateSimplePlatformSupport());
@@ -83,17 +88,23 @@ class EmbedderState {
     sky::shell::Shell::InitStandalone(icu_data_path);
   }
 
+  ~EmbedderState() {
+    CHECK([NSThread isMainThread])
+        << "Embedder destruction must occur on the main platform thread";
+#if !TARGET_OS_IPHONE
+    embedder_message_loop_->QuitNow();
+    embedder_message_loop_.release();
+#endif
+  }
+
  private:
   base::AtExitManager exit_manager_;
-  base::MessageLoopForUI embedder_message_loop_;
+  std::unique_ptr<base::MessageLoopForUI> embedder_message_loop_;
 
   DISALLOW_COPY_AND_ASSIGN(EmbedderState);
 };
 
 void PlatformMacMain(int argc, const char* argv[], std::string icu_data_path) {
-  CHECK([NSThread isMainThread])
-      << "Embedder initialization must occur on the main platform thread";
-
   static std::unique_ptr<EmbedderState> g_embedder;
   static std::once_flag once_main;