Add support for mouse events

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sky/services/pointer/pointer.mojom

@@ -5,6 +5,8 @@
 [DartPackage="sky_services"]
 module pointer;
 
+// See https://github.com/flutter/engine/blob/master/sky/specs/pointer.md
+
 enum PointerType {
   DOWN,
   UP,

sky/shell/platform/glfw/window_impl.cc

@@ -21,11 +21,20 @@ void OnWindowSizeChanged(GLFWwindow* window, int width, int height) {
   ToImpl(window)->UpdateViewportMetrics(width, height);
 }
 
+void OnMouseButtonChanged(GLFWwindow* window, int button, int action, int mods) {
+  ToImpl(window)->DispatchMouseButtonEvent(button, action, mods);
+}
+
+void OnCursorPosChanged(GLFWwindow* window, double x, double y) {
+  ToImpl(window)->DispatchMouseMoveEvent(x, y);
+}
+
 }  // namespace
 
 WindowImpl::WindowImpl(GLFWwindow* window)
     : window_(window),
-      shell_view_(new ShellView(Shell::Shared())) {
+      shell_view_(new ShellView(Shell::Shared())),
+      buttons_(0) {
   glfwSetWindowUserPointer(window_, this);
   auto platform_view =
       static_cast<sky::shell::PlatformViewGLFW*>(shell_view_->view());
@@ -38,6 +47,7 @@ WindowImpl::WindowImpl(GLFWwindow* window)
   UpdateViewportMetrics(width, height);
 
   glfwSetWindowSizeCallback(window_, OnWindowSizeChanged);
+  glfwSetMouseButtonCallback(window_, OnMouseButtonChanged);
 }
 
 WindowImpl::~WindowImpl() {
@@ -61,5 +71,69 @@ void WindowImpl::UpdateViewportMetrics(int width, int height) {
   engine_->OnViewportMetricsChanged(metrics.Pass());
 }
 
+void WindowImpl::DispatchMouseButtonEvent(int button, int action, int mods) {
+  pointer::PointerType type;
+  if (action == GLFW_PRESS) {
+    if (!buttons_) {
+      type = pointer::PointerType::DOWN;
+      glfwSetCursorPosCallback(window_, OnCursorPosChanged);
+    } else {
+      type = pointer::PointerType::MOVE;
+    }
+    // GLFW's button order matches what we want:
+    // https://github.com/flutter/engine/blob/master/sky/specs/pointer.md
+    // http://www.glfw.org/docs/3.2/group__buttons.html
+    buttons_ |= 1 << button;
+  } else if (action == GLFW_RELEASE) {
+    buttons_ &= ~(1 << button);
+    if (!buttons_) {
+      type = pointer::PointerType::UP;
+      glfwSetCursorPosCallback(window_, nullptr);
+    } else {
+      type = pointer::PointerType::MOVE;
+    }
+  } else {
+    DLOG(INFO) << "Unknown mouse action: " << action;
+    return;
+  }
+
+  double x = 0.f, y = 0.f;
+  glfwGetCursorPos(window_, &x, &y);
+
+  base::TimeDelta time_stamp = base::TimeTicks::Now() - base::TimeTicks();
+
+  auto pointer_data = pointer::Pointer::New();
+  pointer_data->time_stamp = time_stamp.InMicroseconds();
+  pointer_data->type = type;
+  pointer_data->kind = pointer::PointerKind::MOUSE;
+  pointer_data->x = x;
+  pointer_data->y = y;
+  pointer_data->buttons = buttons_;
+  pointer_data->pressure = 1.0;
+  pointer_data->pressure_max = 1.0;
+
+  auto pointer_packet = pointer::PointerPacket::New();
+  pointer_packet->pointers.push_back(pointer_data.Pass());
+  engine_->OnPointerPacket(pointer_packet.Pass());
+}
+
+void WindowImpl::DispatchMouseMoveEvent(double x, double y) {
+  base::TimeDelta time_stamp = base::TimeTicks::Now() - base::TimeTicks();
+
+  auto pointer_data = pointer::Pointer::New();
+  pointer_data->time_stamp = time_stamp.InMicroseconds();
+  pointer_data->type = pointer::PointerType::MOVE;
+  pointer_data->kind = pointer::PointerKind::MOUSE;
+  pointer_data->x = x;
+  pointer_data->y = y;
+  pointer_data->buttons = buttons_;
+  pointer_data->pressure = 1.0;
+  pointer_data->pressure_max = 1.0;
+
+  auto pointer_packet = pointer::PointerPacket::New();
+  pointer_packet->pointers.push_back(pointer_data.Pass());
+  engine_->OnPointerPacket(pointer_packet.Pass());
+}
+
 }  // namespace shell
 }  // namespace sky

sky/shell/platform/glfw/window_impl.h

@@ -24,11 +24,14 @@ class WindowImpl {
                      const std::string& bundle_path);
 
   void UpdateViewportMetrics(int width, int height);
+  void DispatchMouseButtonEvent(int button, int action, int mods);
+  void DispatchMouseMoveEvent(double x, double y);
 
  private:
   GLFWwindow* window_;
   std::unique_ptr<ShellView> shell_view_;
   sky::SkyEnginePtr engine_;
+  int buttons_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowImpl);
 };