Split ThreadProxy methods to ProxyMain and ProxyImpl.

cc/trees/thread_proxy.cc

 // Copyright 2011 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 "cc/trees/thread_proxy.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/auto_reset.h"
@@ skipping 120 matching lines @@
   threaded_channel_ = threaded_channel.Pass();
   main().channel_main = threaded_channel_.get();
 }
 
 void ThreadProxy::FinishAllRendering() {
   DCHECK(Proxy::IsMainThread());
   DCHECK(!main().defer_commits);
 
   // Make sure all GL drawing is finished on the impl thread.
   DebugScopedSetMainThreadBlocked main_thread_blocked(this);
-  CompletionEvent completion;
-  Proxy::ImplThreadTaskRunner()->PostTask(
-      FROM_HERE,
-      base::Bind(&ThreadProxy::FinishAllRenderingOnImplThread,
-                 impl_thread_weak_ptr_,
-                 &completion));
-  completion.Wait();
+  main().channel_main->FinishAllRenderingOnImpl();
 }
 
 bool ThreadProxy::IsStarted() const {
   DCHECK(Proxy::IsMainThread());
   return main().started;
 }
 
 bool ThreadProxy::CommitToActiveTree() const {
   // With ThreadProxy, we use a pending tree and activate it once it's ready to
   // draw to allow input to modify the active tree and draw during raster.
   return false;
 }
 
 void ThreadProxy::SetVisible(bool visible) {
   TRACE_EVENT1("cc", "ThreadProxy::SetVisible", "visible", visible);
   DebugScopedSetMainThreadBlocked main_thread_blocked(this);
 
-  CompletionEvent completion;
-  Proxy::ImplThreadTaskRunner()->PostTask(
-      FROM_HERE,
-      base::Bind(&ThreadProxy::SetVisibleOnImplThread,
-                 impl_thread_weak_ptr_,
-                 &completion,
-                 visible));
-  completion.Wait();
+  main().channel_main->SetVisibleOnImpl(visible);

[danakj, 2015/10/08 19:21:08]

i'd like it if it was obvious which calls are going to block or not.

can you maybe prefix or suffix all such waiting calls with Synchronous?

[Khushal, 2015/10/08 20:32:07]

We will try to make some calls asynchronous for Blimp. For instance, when
starting the commit on impl, we send the serialized commit state of the Layer
Tree to the client to commit from, after this the main thread will not be
blocked. This is why I was trying to limit this within the channel
implementation.

Should I still consider marking it as synchronous in the channel interface?

[danakj, 2015/10/09 17:54:43]

I think we should mark everything as Sync that is sync right now. For the
commit, perhaps it would split into two separate steps in the proxy.

1) SendCommitStuff
2) SendCommitStuffSync

or whatever. Non-blimp would use the sync version. Then it's obvious at
callsites what the behaviour will be.

[Khushal, 2015/10/09 19:46:55]

That would definitely be better. Just had one doubt, since the details of
whether the Proxy is using an implementation of the channel for chrome or for
blimp is completely abstracted by the channel interface, we'd need something in
Proxy to decide whether it uses a sync or non-sync method.

Would be want to add this as a setting to ProxyMain?

 }
 
-void ThreadProxy::SetVisibleOnImplThread(CompletionEvent* completion,
-                                         bool visible) {
+void ThreadProxy::SetVisibleOnImpl(bool visible) {
   TRACE_EVENT1("cc", "ThreadProxy::SetVisibleOnImplThread", "visible", visible);
   impl().layer_tree_host_impl->SetVisible(visible);
   impl().scheduler->SetVisible(visible);
-  completion->Signal();
 }
 
 void ThreadProxy::SetThrottleFrameProduction(bool throttle) {
   TRACE_EVENT1("cc", "ThreadProxy::SetThrottleFrameProduction", "throttle",
                throttle);
   main().channel_main->SetThrottleFrameProductionOnImpl(throttle);
 }
 
 void ThreadProxy::SetThrottleFrameProductionOnImpl(bool throttle) {
   TRACE_EVENT1("cc", "ThreadProxy::SetThrottleFrameProductionOnImplThread",
                "throttle", throttle);
   impl().scheduler->SetThrottleFrameProduction(throttle);
 }
 
 void ThreadProxy::DidLoseOutputSurface() {
   TRACE_EVENT0("cc", "ThreadProxy::DidLoseOutputSurface");
   DCHECK(IsMainThread());
   layer_tree_host()->DidLoseOutputSurface();
 }
 
 void ThreadProxy::RequestNewOutputSurface() {
   DCHECK(IsMainThread());
   layer_tree_host()->RequestNewOutputSurface();
 }
 
 void ThreadProxy::SetOutputSurface(OutputSurface* output_surface) {
-  Proxy::ImplThreadTaskRunner()->PostTask(
-      FROM_HERE, base::Bind(&ThreadProxy::InitializeOutputSurfaceOnImplThread,
-                            impl_thread_weak_ptr_, output_surface));
+  main().channel_main->InitializeOutputSurfaceOnImpl(output_surface);
 }
 
 void ThreadProxy::ReleaseOutputSurface() {
   DCHECK(IsMainThread());
   DCHECK(layer_tree_host()->output_surface_lost());
 
   DebugScopedSetMainThreadBlocked main_thread_blocked(this);
-  CompletionEvent completion;
-  Proxy::ImplThreadTaskRunner()->PostTask(
-      FROM_HERE, base::Bind(&ThreadProxy::ReleaseOutputSurfaceOnImplThread,
-                            impl_thread_weak_ptr_, &completion));
-  completion.Wait();
+  main().channel_main->ReleaseOutputSurfaceOnImpl();
 }
 
 void ThreadProxy::DidInitializeOutputSurface(
     bool success,
     const RendererCapabilities& capabilities) {
   TRACE_EVENT0("cc", "ThreadProxy::DidInitializeOutputSurface");
   DCHECK(IsMainThread());
 
   if (!success) {
     layer_tree_host()->DidFailToInitializeOutputSurface();
     return;
   }
   main().renderer_capabilities_main_thread_copy = capabilities;
   layer_tree_host()->DidInitializeOutputSurface();
 }
 
-void ThreadProxy::SetRendererCapabilitiesMainThreadCopy(
+void ThreadProxy::SetRendererCapabilitiesMainCopy(
     const RendererCapabilities& capabilities) {
   main().renderer_capabilities_main_thread_copy = capabilities;
 }
 
 bool ThreadProxy::SendCommitRequestToImplThreadIfNeeded(
     CommitPipelineStage required_stage) {
   DCHECK(IsMainThread());
   DCHECK_NE(NO_PIPELINE_STAGE, required_stage);
   bool already_posted =
       main().max_requested_pipeline_stage != NO_PIPELINE_STAGE;
@@ skipping 52 matching lines @@
     return;
   }
   if (SendCommitRequestToImplThreadIfNeeded(COMMIT_PIPELINE_STAGE)) {
     TRACE_EVENT_INSTANT0("cc", "ThreadProxy::SetNeedsCommit",
                          TRACE_EVENT_SCOPE_THREAD);
   }
 }
 
 void ThreadProxy::UpdateRendererCapabilitiesOnImplThread() {
   DCHECK(IsImplThread());
-  Proxy::MainThreadTaskRunner()->PostTask(
-      FROM_HERE,
-      base::Bind(&ThreadProxy::SetRendererCapabilitiesMainThreadCopy,
-                 main_thread_weak_ptr_,
-                 impl()
-                     .layer_tree_host_impl->GetRendererCapabilities()
-                     .MainThreadCapabilities()));
+  impl().channel_impl->SetRendererCapabilitiesMainCopy(
+      impl()
+          .layer_tree_host_impl->GetRendererCapabilities()
+          .MainThreadCapabilities());
 }
 
 void ThreadProxy::DidLoseOutputSurfaceOnImplThread() {
   TRACE_EVENT0("cc", "ThreadProxy::DidLoseOutputSurfaceOnImplThread");
   DCHECK(IsImplThread());
-  Proxy::MainThreadTaskRunner()->PostTask(
-      FROM_HERE,
-      base::Bind(&ThreadProxy::DidLoseOutputSurface, main_thread_weak_ptr_));
+  impl().channel_impl->DidLoseOutputSurface();
   impl().scheduler->DidLoseOutputSurface();
 }
 
 void ThreadProxy::CommitVSyncParameters(base::TimeTicks timebase,
                                         base::TimeDelta interval) {
   impl().scheduler->CommitVSyncParameters(timebase, interval);
 }
 
 void ThreadProxy::SetEstimatedParentDrawTime(base::TimeDelta draw_time) {
   impl().scheduler->SetEstimatedParentDrawTime(draw_time);
@@ skipping 59 matching lines @@
   // In tests the layer tree is destroyed after the scheduler is.
   if (impl().scheduler)
     impl().scheduler->SetVideoNeedsBeginFrames(needs_begin_frames);
 }
 
 void ThreadProxy::PostAnimationEventsToMainThreadOnImplThread(
     scoped_ptr<AnimationEventsVector> events) {
   TRACE_EVENT0("cc",
                "ThreadProxy::PostAnimationEventsToMainThreadOnImplThread");
   DCHECK(IsImplThread());
-  Proxy::MainThreadTaskRunner()->PostTask(
-      FROM_HERE,
-      base::Bind(&ThreadProxy::SetAnimationEvents,
-                 main_thread_weak_ptr_,
-                 base::Passed(&events)));
+  impl().channel_impl->SetAnimationEvents(events.Pass());
 }
 
 bool ThreadProxy::IsInsideDraw() { return impl().inside_draw; }
 
 void ThreadProxy::SetNeedsRedraw(const gfx::Rect& damage_rect) {
   TRACE_EVENT0("cc", "ThreadProxy::SetNeedsRedraw");
   DCHECK(IsMainThread());
   Proxy::ImplThreadTaskRunner()->PostTask(
       FROM_HERE,
       base::Bind(&ThreadProxy::SetNeedsRedrawRectOnImplThread,
@@ skipping 11 matching lines @@
   DCHECK(IsMainThread());
   if (main().defer_commits == defer_commits)
     return;
 
   main().defer_commits = defer_commits;
   if (main().defer_commits)
     TRACE_EVENT_ASYNC_BEGIN0("cc", "ThreadProxy::SetDeferCommits", this);
   else
     TRACE_EVENT_ASYNC_END0("cc", "ThreadProxy::SetDeferCommits", this);
 
-  Proxy::ImplThreadTaskRunner()->PostTask(
-      FROM_HERE,
-      base::Bind(&ThreadProxy::SetDeferCommitsOnImplThread,
-                 impl_thread_weak_ptr_,
-                 defer_commits));
+  main().channel_main->SetDeferCommitsOnImpl(defer_commits);
 }
 
-void ThreadProxy::SetDeferCommitsOnImplThread(bool defer_commits) const {
+void ThreadProxy::SetDeferCommitsOnImpl(bool defer_commits) {
   DCHECK(IsImplThread());
   impl().scheduler->SetDeferCommits(defer_commits);
 }
 
 bool ThreadProxy::CommitRequested() const {
   DCHECK(IsMainThread());
   // TODO(skyostil): Split this into something like CommitRequested() and
   // CommitInProgress().
   return main().current_pipeline_stage != NO_PIPELINE_STAGE ||
          main().max_requested_pipeline_stage >= COMMIT_PIPELINE_STAGE;
@@ skipping 22 matching lines @@
 }
 
 void ThreadProxy::SetNeedsRedrawRectOnImplThread(const gfx::Rect& damage_rect) {
   DCHECK(IsImplThread());
   impl().layer_tree_host_impl->SetViewportDamage(damage_rect);
   SetNeedsRedrawOnImplThread();
 }
 
 void ThreadProxy::MainThreadHasStoppedFlinging() {
   DCHECK(IsMainThread());
-  Proxy::ImplThreadTaskRunner()->PostTask(
-      FROM_HERE,
-      base::Bind(&ThreadProxy::MainThreadHasStoppedFlingingOnImplThread,
-                 impl_thread_weak_ptr_));
+  main().channel_main->MainThreadHasStoppedFlingingOnImpl();
 }
 
-void ThreadProxy::MainThreadHasStoppedFlingingOnImplThread() {
+void ThreadProxy::MainThreadHasStoppedFlingingOnImpl() {
   DCHECK(IsImplThread());
   impl().layer_tree_host_impl->MainThreadHasStoppedFlinging();
 }
 
 void ThreadProxy::NotifyInputThrottledUntilCommit() {
   DCHECK(IsMainThread());
-  Proxy::ImplThreadTaskRunner()->PostTask(
-      FROM_HERE,
-      base::Bind(&ThreadProxy::SetInputThrottledUntilCommitOnImplThread,
-                 impl_thread_weak_ptr_,
-                 true));
+  main().channel_main->SetInputThrottledUntilCommitOnImpl(true);
 }
 
-void ThreadProxy::SetInputThrottledUntilCommitOnImplThread(bool is_throttled) {
+void ThreadProxy::SetInputThrottledUntilCommitOnImpl(bool is_throttled) {
   DCHECK(IsImplThread());
   if (is_throttled == impl().input_throttled_until_commit)
     return;
   impl().input_throttled_until_commit = is_throttled;
   RenewTreePriority();
 }
 
 LayerTreeHost* ThreadProxy::layer_tree_host() {
   return blocked_main().layer_tree_host;
 }
@@ skipping 55 matching lines @@
   TRACE_EVENT0("cc", "ThreadProxy::Stop");
   DCHECK(IsMainThread());
   DCHECK(main().started);
 
   // Synchronously finishes pending GL operations and deletes the impl.
   // The two steps are done as separate post tasks, so that tasks posted
   // by the GL implementation due to the Finish can be executed by the
   // renderer before shutting it down.
   {
     DebugScopedSetMainThreadBlocked main_thread_blocked(this);
-
-    CompletionEvent completion;
-    Proxy::ImplThreadTaskRunner()->PostTask(
-        FROM_HERE,
-        base::Bind(&ThreadProxy::FinishGLOnImplThread,
-                   impl_thread_weak_ptr_,
-                   &completion));
-    completion.Wait();
+    main().channel_main->FinishGLOnImpl();
   }
   {
     DebugScopedSetMainThreadBlocked main_thread_blocked(this);
 
     CompletionEvent completion;
     Proxy::ImplThreadTaskRunner()->PostTask(
         FROM_HERE,
         base::Bind(&ThreadProxy::LayerTreeHostClosedOnImplThread,
                    impl_thread_weak_ptr_,
                    &completion));
     completion.Wait();
   }
 
   main().weak_factory.InvalidateWeakPtrs();
   blocked_main().layer_tree_host = NULL;
   main().started = false;
 }
 
 bool ThreadProxy::SupportsImplScrolling() const {
   return true;
 }
 
-void ThreadProxy::FinishAllRenderingOnImplThread(CompletionEvent* completion) {
+void ThreadProxy::FinishAllRenderingOnImpl() {
   TRACE_EVENT0("cc", "ThreadProxy::FinishAllRenderingOnImplThread");
   DCHECK(IsImplThread());
   impl().layer_tree_host_impl->FinishAllRendering();
-  completion->Signal();
 }
 
 void ThreadProxy::ScheduledActionSendBeginMainFrame() {
   unsigned int begin_frame_id = nextBeginFrameId++;
   benchmark_instrumentation::ScopedBeginFrameTask begin_frame_task(
       benchmark_instrumentation::kSendBeginFrame, begin_frame_id);
   scoped_ptr<BeginMainFrameAndCommitState> begin_main_frame_state(
       new BeginMainFrameAndCommitState);
   begin_main_frame_state->begin_frame_id = begin_frame_id;
   begin_main_frame_state->begin_frame_args =
@@ skipping 11 matching lines @@
   Proxy::MainThreadTaskRunner()->PostTask(
       FROM_HERE,
       base::Bind(&ThreadProxy::BeginMainFrame,
                  main_thread_weak_ptr_,
                  base::Passed(&begin_main_frame_state)));
   devtools_instrumentation::DidRequestMainThreadFrame(
       impl().layer_tree_host_id);
 }
 
 void ThreadProxy::SendBeginMainFrameNotExpectedSoon() {
-  Proxy::MainThreadTaskRunner()->PostTask(
-      FROM_HERE, base::Bind(&ThreadProxy::BeginMainFrameNotExpectedSoon,
-                            main_thread_weak_ptr_));
+  impl().channel_impl->BeginMainFrameNotExpectedSoon();
 }
 
 void ThreadProxy::BeginMainFrame(
     scoped_ptr<BeginMainFrameAndCommitState> begin_main_frame_state) {
   benchmark_instrumentation::ScopedBeginFrameTask begin_frame_task(
       benchmark_instrumentation::kDoBeginFrame,
       begin_main_frame_state->begin_frame_id);
   TRACE_EVENT_SYNTHETIC_DELAY_BEGIN("cc.BeginMainFrame");
   DCHECK(IsMainThread());
   DCHECK_EQ(NO_PIPELINE_STAGE, main().current_pipeline_stage);
@@ skipping 143 matching lines @@
 void ThreadProxy::BeginMainFrameAbortedOnImplThread(
     CommitEarlyOutReason reason) {
   TRACE_EVENT1("cc", "ThreadProxy::BeginMainFrameAbortedOnImplThread", "reason",
                CommitEarlyOutReasonToString(reason));
   DCHECK(IsImplThread());
   DCHECK(impl().scheduler);
   DCHECK(impl().scheduler->CommitPending());
   DCHECK(!impl().layer_tree_host_impl->pending_tree());
 
   if (CommitEarlyOutHandledCommit(reason)) {
-    SetInputThrottledUntilCommitOnImplThread(false);
+    SetInputThrottledUntilCommitOnImpl(false);
     impl().last_processed_begin_main_frame_args =
         impl().last_begin_main_frame_args;
   }
   impl().layer_tree_host_impl->BeginMainFrameAborted(reason);
   impl().scheduler->BeginMainFrameAborted(reason);
 }
 
 void ThreadProxy::ScheduledActionAnimate() {
   TRACE_EVENT0("cc", "ThreadProxy::ScheduledActionAnimate");
   DCHECK(IsImplThread());
@@ skipping 28 matching lines @@
     impl().commit_completion_event->Signal();
     impl().commit_completion_event = NULL;
   }
 
   impl().scheduler->DidCommit();
 
   // Delay this step until afer the main thread has been released as it's
   // often a good bit of work to update the tree and prepare the new frame.
   impl().layer_tree_host_impl->CommitComplete();
 
-  SetInputThrottledUntilCommitOnImplThread(false);
+  SetInputThrottledUntilCommitOnImpl(false);
 
   impl().next_frame_is_newly_committed_frame = true;
 }
 
 void ThreadProxy::ScheduledActionActivateSyncTree() {
   TRACE_EVENT0("cc", "ThreadProxy::ScheduledActionActivateSyncTree");
   DCHECK(IsImplThread());
   impl().layer_tree_host_impl->ActivateSyncTree();
 }
 
 void ThreadProxy::ScheduledActionBeginOutputSurfaceCreation() {
   TRACE_EVENT0("cc", "ThreadProxy::ScheduledActionBeginOutputSurfaceCreation");
   DCHECK(IsImplThread());
-  Proxy::MainThreadTaskRunner()->PostTask(
-      FROM_HERE,
-      base::Bind(&ThreadProxy::RequestNewOutputSurface, main_thread_weak_ptr_));
+  impl().channel_impl->RequestNewOutputSurface();
 }
 
 DrawResult ThreadProxy::DrawSwapInternal(bool forced_draw) {
   TRACE_EVENT_SYNTHETIC_DELAY("cc.DrawAndSwap");
   DrawResult result;
 
   DCHECK(IsImplThread());
   DCHECK(impl().layer_tree_host_impl.get());
 
   base::AutoReset<bool> mark_inside(&impl().inside_draw, true);
@@ skipping 35 matching lines @@
 
   bool start_ready_animations = draw_frame;
   impl().layer_tree_host_impl->UpdateAnimationState(start_ready_animations);
 
   if (draw_frame)
     impl().layer_tree_host_impl->SwapBuffers(frame);
 
   // Tell the main thread that the the newly-commited frame was drawn.
   if (impl().next_frame_is_newly_committed_frame) {
     impl().next_frame_is_newly_committed_frame = false;
-    Proxy::MainThreadTaskRunner()->PostTask(
-        FROM_HERE,
-        base::Bind(&ThreadProxy::DidCommitAndDrawFrame, main_thread_weak_ptr_));
+    impl().channel_impl->DidCommitAndDrawFrame();
   }
 
   DCHECK_NE(INVALID_RESULT, result);
   return result;
 }
 
 void ThreadProxy::ScheduledActionPrepareTiles() {
   TRACE_EVENT0("cc", "ThreadProxy::ScheduledActionPrepareTiles");
   impl().layer_tree_host_impl->PrepareTiles();
 }
@@ skipping 70 matching lines @@
                                   impl().rendering_stats_instrumentation));
 
   impl().scheduler = Scheduler::Create(
       this, scheduler_settings, impl().layer_tree_host_id,
       ImplThreadTaskRunner(), impl().external_begin_frame_source.get(),
       compositor_timing_history.Pass());
 
   DCHECK_EQ(impl().scheduler->visible(),
             impl().layer_tree_host_impl->visible());
   impl_thread_weak_ptr_ = impl().weak_factory.GetWeakPtr();
+  threaded_channel_->InitImplThreadWeakPtr();
   completion->Signal();
 }
 
-void ThreadProxy::InitializeOutputSurfaceOnImplThread(
-    OutputSurface* output_surface) {
+void ThreadProxy::InitializeOutputSurfaceOnImpl(OutputSurface* output_surface) {
   TRACE_EVENT0("cc", "ThreadProxy::InitializeOutputSurfaceOnImplThread");
   DCHECK(IsImplThread());
 
   LayerTreeHostImpl* host_impl = impl().layer_tree_host_impl.get();
   bool success = host_impl->InitializeRenderer(output_surface);
   RendererCapabilities capabilities;
   if (success) {
     capabilities =
         host_impl->GetRendererCapabilities().MainThreadCapabilities();
   }
 
-  Proxy::MainThreadTaskRunner()->PostTask(
-      FROM_HERE,
-      base::Bind(&ThreadProxy::DidInitializeOutputSurface,
-                 main_thread_weak_ptr_,
-                 success,
-                 capabilities));
+  impl().channel_impl->DidInitializeOutputSurface(success, capabilities);
 
   if (success)
     impl().scheduler->DidCreateAndInitializeOutputSurface();
 }
 
-void ThreadProxy::ReleaseOutputSurfaceOnImplThread(
-    CompletionEvent* completion) {
+void ThreadProxy::ReleaseOutputSurfaceOnImpl() {
   DCHECK(IsImplThread());
 
   // Unlike DidLoseOutputSurfaceOnImplThread, we don't need to call
   // LayerTreeHost::DidLoseOutputSurface since it already knows.
   impl().scheduler->DidLoseOutputSurface();
   impl().layer_tree_host_impl->ReleaseOutputSurface();
-  completion->Signal();
 }
 
-void ThreadProxy::FinishGLOnImplThread(CompletionEvent* completion) {
+void ThreadProxy::FinishGLOnImpl() {
   TRACE_EVENT0("cc", "ThreadProxy::FinishGLOnImplThread");
   DCHECK(IsImplThread());
   if (impl().layer_tree_host_impl->output_surface()) {
     ContextProvider* context_provider =
         impl().layer_tree_host_impl->output_surface()->context_provider();
     if (context_provider)
       context_provider->ContextGL()->Finish();
   }
-  completion->Signal();
 }
 
 void ThreadProxy::LayerTreeHostClosedOnImplThread(CompletionEvent* completion) {
   TRACE_EVENT0("cc", "ThreadProxy::LayerTreeHostClosedOnImplThread");
   DCHECK(IsImplThread());
   DCHECK(IsMainThreadBlocked());
   impl().scheduler = nullptr;
   impl().external_begin_frame_source = nullptr;
   impl().layer_tree_host_impl = nullptr;
   impl().weak_factory.InvalidateWeakPtrs();
+  threaded_channel_->InvalidateImplThreadWeakPtr();
   // We need to explicitly shutdown the notifier to destroy any weakptrs it is
   // holding while still on the compositor thread. This also ensures any
   // callbacks holding a ThreadProxy pointer are cancelled.
   impl().smoothness_priority_expiration_notifier.Shutdown();
   completion->Signal();
 }
 
 ThreadProxy::BeginMainFrameAndCommitState::BeginMainFrameAndCommitState()
     : memory_allocation_limit_bytes(0),
       evicted_ui_resources(false) {}
 
 ThreadProxy::BeginMainFrameAndCommitState::~BeginMainFrameAndCommitState() {}
 
 bool ThreadProxy::MainFrameWillHappenForTesting() {
   DCHECK(IsMainThread());
-  CompletionEvent completion;
   bool main_frame_will_happen = false;
   {
     DebugScopedSetMainThreadBlocked main_thread_blocked(this);
-    Proxy::ImplThreadTaskRunner()->PostTask(
-        FROM_HERE,
-        base::Bind(&ThreadProxy::MainFrameWillHappenOnImplThreadForTesting,
-                   impl_thread_weak_ptr_,
-                   &completion,
-                   &main_frame_will_happen));
-    completion.Wait();
+    main().channel_main->MainFrameWillHappenOnImplForTesting(
+        &main_frame_will_happen);
   }
   return main_frame_will_happen;
 }
 
 void ThreadProxy::SetChildrenNeedBeginFrames(bool children_need_begin_frames) {
   NOTREACHED() << "Only used by SingleThreadProxy";
 }
 
-void ThreadProxy::MainFrameWillHappenOnImplThreadForTesting(
-    CompletionEvent* completion,
+void ThreadProxy::MainFrameWillHappenOnImplForTesting(
     bool* main_frame_will_happen) {
   DCHECK(IsImplThread());
   if (impl().layer_tree_host_impl->output_surface()) {
     *main_frame_will_happen = impl().scheduler->MainFrameForTestingWillHappen();
   } else {
     *main_frame_will_happen = false;
   }
-  completion->Signal();
 }
 
 void ThreadProxy::RenewTreePriority() {
   DCHECK(IsImplThread());
   bool smoothness_takes_priority =
       impl().layer_tree_host_impl->pinch_gesture_active() ||
       impl().layer_tree_host_impl->page_scale_animation_active() ||
       impl().layer_tree_host_impl->IsActivelyScrolling();
 
   // Schedule expiration if smoothness currently takes priority.
@@ skipping 65 matching lines @@
   impl().scheduler->WillPrepareTiles();
 }
 
 void ThreadProxy::DidPrepareTiles() {
   DCHECK(IsImplThread());
   impl().scheduler->DidPrepareTiles();
 }
 
 void ThreadProxy::DidCompletePageScaleAnimationOnImplThread() {
   DCHECK(IsImplThread());
-  Proxy::MainThreadTaskRunner()->PostTask(
-      FROM_HERE, base::Bind(&ThreadProxy::DidCompletePageScaleAnimation,
-                            main_thread_weak_ptr_));
+  impl().channel_impl->DidCompletePageScaleAnimation();
 }
 
 void ThreadProxy::OnDrawForOutputSurface() {
   DCHECK(IsImplThread());
   impl().scheduler->OnDrawForOutputSurface();
 }
 
 void ThreadProxy::PostFrameTimingEventsOnImplThread(
     scoped_ptr<FrameTimingTracker::CompositeTimingSet> composite_events,
     scoped_ptr<FrameTimingTracker::MainFrameTimingSet> main_frame_events) {
   DCHECK(IsImplThread());
-  Proxy::MainThreadTaskRunner()->PostTask(
-      FROM_HERE,
-      base::Bind(&ThreadProxy::PostFrameTimingEvents, main_thread_weak_ptr_,
-                 base::Passed(composite_events.Pass()),
-                 base::Passed(main_frame_events.Pass())));
+  impl().channel_impl->PostFrameTimingEventsOnMain(composite_events.Pass(),
+                                                   main_frame_events.Pass());
 }
 
-void ThreadProxy::PostFrameTimingEvents(
+void ThreadProxy::PostFrameTimingEventsOnMain(
     scoped_ptr<FrameTimingTracker::CompositeTimingSet> composite_events,
     scoped_ptr<FrameTimingTracker::MainFrameTimingSet> main_frame_events) {
   DCHECK(IsMainThread());
   layer_tree_host()->RecordFrameTimingEvents(composite_events.Pass(),
                                              main_frame_events.Pass());
 }
 
 base::WeakPtr<ProxyMain> ThreadProxy::GetMainWeakPtr() {
   return main_thread_weak_ptr_;
 }
 
 base::WeakPtr<ProxyImpl> ThreadProxy::GetImplWeakPtr() {
   return impl_thread_weak_ptr_;
 }
 
 }  // namespace cc