cc: Split Proxy and TaskRunnerProvider for the LayerTreeHost

cc/trees/layer_tree_host.cc

Index: cc/trees/layer_tree_host.cc
diff --git a/cc/trees/layer_tree_host.cc b/cc/trees/layer_tree_host.cc
index 8312165c1165b6ae8bd1271e106eed1d0f3c04f2..74dc211045a01d8f229ce22cd0ab28ab45af6cb1 100644
--- a/cc/trees/layer_tree_host.cc
+++ b/cc/trees/layer_tree_host.cc
@@ -137,9 +137,9 @@ void LayerTreeHost::InitializeThreaded(
     scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
     scoped_refptr<base::SingleThreadTaskRunner> impl_task_runner,
     scoped_ptr<BeginFrameSource> external_begin_frame_source) {
-  InitializeProxy(ThreadProxy::Create(this,
-                                      main_task_runner,
-                                      impl_task_runner,
+  task_runner_provider_ =
+      TaskRunnerProvider::Create(main_task_runner, impl_task_runner);
+  InitializeProxy(ThreadProxy::Create(this, task_runner_provider_.get(),
                                       external_begin_frame_source.Pass()));
 }
 
@@ -147,14 +147,16 @@ void LayerTreeHost::InitializeSingleThreaded(
     LayerTreeHostSingleThreadClient* single_thread_client,
     scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
     scoped_ptr<BeginFrameSource> external_begin_frame_source) {
-  InitializeProxy(
-      SingleThreadProxy::Create(this,
-                                single_thread_client,
-                                main_task_runner,
-                                external_begin_frame_source.Pass()));
+  task_runner_provider_ = TaskRunnerProvider::Create(main_task_runner, nullptr);
+  InitializeProxy(SingleThreadProxy::Create(
+      this, single_thread_client, task_runner_provider_.get(),
+      external_begin_frame_source.Pass()));
 }
 
-void LayerTreeHost::InitializeForTesting(scoped_ptr<Proxy> proxy_for_testing) {
+void LayerTreeHost::InitializeForTesting(
+    scoped_ptr<TaskRunnerProvider> task_runner_provider,
+    scoped_ptr<Proxy> proxy_for_testing) {
+  task_runner_provider_ = task_runner_provider.Pass();
   InitializeProxy(proxy_for_testing.Pass());
 }
 
@@ -187,8 +189,11 @@ LayerTreeHost::~LayerTreeHost() {
   BreakSwapPromises(SwapPromise::COMMIT_FAILS);
 
   if (proxy_) {
-    DCHECK(proxy_->IsMainThread());
+    DCHECK(task_runner_provider_->IsMainThread());
     proxy_->Stop();
+
+    // Proxy must be destroyed before the Task Runner Provider.
+    proxy_ = nullptr;
   }
 
   // We must clear any pointers into the layer tree prior to destroying it.
@@ -234,7 +239,7 @@ void LayerTreeHost::RequestMainFrameUpdate() {
 // should be delayed until the LayerTreeHost::CommitComplete, which will run
 // after the commit, but on the main thread.
 void LayerTreeHost::FinishCommitOnImplThread(LayerTreeHostImpl* host_impl) {
-  DCHECK(proxy_->IsImplThread());
+  DCHECK(task_runner_provider_->IsImplThread());
 
   bool is_new_trace;
   TRACE_EVENT_IS_NEW_TRACE(&is_new_trace);
@@ -419,11 +424,11 @@ void LayerTreeHost::DidFailToInitializeOutputSurface() {
 
 scoped_ptr<LayerTreeHostImpl> LayerTreeHost::CreateLayerTreeHostImpl(
     LayerTreeHostImplClient* client) {
-  DCHECK(proxy_->IsImplThread());
+  DCHECK(task_runner_provider_->IsImplThread());
   scoped_ptr<LayerTreeHostImpl> host_impl = LayerTreeHostImpl::Create(
-      settings_, client, proxy_.get(), rendering_stats_instrumentation_.get(),
-      shared_bitmap_manager_, gpu_memory_buffer_manager_, task_graph_runner_,
-      id_);
+      settings_, client, task_runner_provider_.get(),
+      rendering_stats_instrumentation_.get(), shared_bitmap_manager_,
+      gpu_memory_buffer_manager_, task_graph_runner_, id_);
   host_impl->SetHasGpuRasterizationTrigger(has_gpu_rasterization_trigger_);
   host_impl->SetContentIsSuitableForGpuRasterization(
       content_is_suitable_for_gpu_rasterization_);
@@ -436,7 +441,7 @@ scoped_ptr<LayerTreeHostImpl> LayerTreeHost::CreateLayerTreeHostImpl(
 
 void LayerTreeHost::DidLoseOutputSurface() {
   TRACE_EVENT0("cc", "LayerTreeHost::DidLoseOutputSurface");
-  DCHECK(proxy_->IsMainThread());
+  DCHECK(task_runner_provider_->IsMainThread());
 
   if (output_surface_lost_)
     return;
@@ -530,7 +535,7 @@ void LayerTreeHost::SetNextCommitForcesRedraw() {
 
 void LayerTreeHost::SetAnimationEvents(
     scoped_ptr<AnimationEventsVector> events) {
-  DCHECK(proxy_->IsMainThread());
+  DCHECK(task_runner_provider_->IsMainThread());
   if (animation_host_)
     animation_host_->SetAnimationEvents(events.Pass());
   else
@@ -668,7 +673,7 @@ void LayerTreeHost::NotifyInputThrottledUntilCommit() {
 }
 
 void LayerTreeHost::LayoutAndUpdateLayers() {
-  DCHECK(!proxy_->HasImplThread());
+  DCHECK(!task_runner_provider_->HasImplThread());
   // This function is only valid when not using the scheduler.
   DCHECK(!settings_.single_thread_proxy_scheduler);
   SingleThreadProxy* proxy = static_cast<SingleThreadProxy*>(proxy_.get());
@@ -686,7 +691,7 @@ void LayerTreeHost::LayoutAndUpdateLayers() {
 }
 
 void LayerTreeHost::Composite(base::TimeTicks frame_begin_time) {
-  DCHECK(!proxy_->HasImplThread());
+  DCHECK(!task_runner_provider_->HasImplThread());
   // This function is only valid when not using the scheduler.
   DCHECK(!settings_.single_thread_proxy_scheduler);
   SingleThreadProxy* proxy = static_cast<SingleThreadProxy*>(proxy_.get());
@@ -727,7 +732,8 @@ static Layer* FindFirstScrollableLayer(Layer* layer) {
 void LayerTreeHost::RecordGpuRasterizationHistogram() {
   // Gpu rasterization is only supported for Renderer compositors.
   // Checking for proxy_->HasImplThread() to exclude Browser compositors.
-  if (gpu_rasterization_histogram_recorded_ || !proxy_->HasImplThread())
+  if (gpu_rasterization_histogram_recorded_ ||
+      !task_runner_provider_->HasImplThread())
     return;
 
   // Record how widely gpu rasterization is enabled.
@@ -895,7 +901,7 @@ void LayerTreeHost::UpdateTopControlsState(TopControlsState constraints,
                                            TopControlsState current,
                                            bool animate) {
   // Top controls are only used in threaded mode.
-  DCHECK(proxy_->HasImplThread());
+  DCHECK(task_runner_provider_->HasImplThread());
   proxy_->UpdateTopControlsState(constraints, current, animate);
 }