[exo] Clean up BeginFrame distribution & add acks in Surface.

components/exo/compositor_frame_sink_holder.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 "components/exo/compositor_frame_sink_holder.h"
 
 #include "cc/resources/returned_resource.h"
 #include "components/exo/surface.h"
 
 namespace exo {
 
 ////////////////////////////////////////////////////////////////////////////////
 // CompositorFrameSinkHolder, public:
 
 CompositorFrameSinkHolder::CompositorFrameSinkHolder(
     Surface* surface,
     const cc::FrameSinkId& frame_sink_id,
     cc::SurfaceManager* surface_manager)
     : surface_(surface),
       frame_sink_(
           new CompositorFrameSink(frame_sink_id, surface_manager, this)),
       begin_frame_source_(base::MakeUnique<cc::ExternalBeginFrameSource>(this)),
       weak_factory_(this) {
   surface_->AddSurfaceObserver(this);
+  surface_->SetBeginFrameSource(begin_frame_source_.get());
 }
 
 bool CompositorFrameSinkHolder::HasReleaseCallbackForResource(
     cc::ResourceId id) {
   return release_callbacks_.find(id) != release_callbacks_.end();
 }
 
 void CompositorFrameSinkHolder::SetResourceReleaseCallback(
     cc::ResourceId id,
     const cc::ReleaseCallback& callback) {
   DCHECK(!callback.is_null());
   release_callbacks_[id] = callback;
 }
 
-void CompositorFrameSinkHolder::SetNeedsBeginFrame(bool needs_begin_frame) {
-  needs_begin_frame_ = needs_begin_frame;
-  OnNeedsBeginFrames(needs_begin_frame);
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // cc::mojom::MojoCompositorFrameSinkClient overrides:
 
 void CompositorFrameSinkHolder::DidReceiveCompositorFrameAck() {
   // TODO(staraz): Implement this
 }
 
 void CompositorFrameSinkHolder::OnBeginFrame(const cc::BeginFrameArgs& args) {
-  // TODO(eseckler): Hook up |surface_| to the ExternalBeginFrameSource.
-  if (surface_)
-    surface_->BeginFrame(args.frame_time);
-
   begin_frame_source_->OnBeginFrame(args);
 }
 
 void CompositorFrameSinkHolder::ReclaimResources(
     const cc::ReturnedResourceArray& resources) {
   for (auto& resource : resources) {
     auto it = release_callbacks_.find(resource.id);
     DCHECK(it != release_callbacks_.end());
     if (it != release_callbacks_.end()) {
       it->second.Run(resource.sync_token, resource.lost);
       release_callbacks_.erase(it);
     }
   }
 }
 
 void CompositorFrameSinkHolder::WillDrawSurface(
     const cc::LocalSurfaceId& local_surface_id,
     const gfx::Rect& damage_rect) {
   if (surface_)
     surface_->WillDraw();
-
-  UpdateNeedsBeginFrame();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-// cc::BeginFrameObserver overrides:
-
-const cc::BeginFrameArgs& CompositorFrameSinkHolder::LastUsedBeginFrameArgs()
-    const {
-  return last_begin_frame_args_;
-}
-
-void CompositorFrameSinkHolder::OnBeginFrameSourcePausedChanged(bool paused) {}
-
-////////////////////////////////////////////////////////////////////////////////
-// cc::ExternalBeginFrameSouceClient overrides:
+// cc::ExternalBeginFrameSourceClient overrides:
 
 void CompositorFrameSinkHolder::OnNeedsBeginFrames(bool needs_begin_frames) {
   frame_sink_->SetNeedsBeginFrame(needs_begin_frames);
 }
 
 void CompositorFrameSinkHolder::OnDidFinishFrame(const cc::BeginFrameAck& ack) {
   // TODO(eseckler): Pass on the ack to frame_sink_.
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // SurfaceObserver overrides:
 
 void CompositorFrameSinkHolder::OnSurfaceDestroying(Surface* surface) {
   surface_->RemoveSurfaceObserver(this);
   surface_ = nullptr;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // ExoComopositorFrameSink, private:
 
 CompositorFrameSinkHolder::~CompositorFrameSinkHolder() {
   if (surface_)
     surface_->RemoveSurfaceObserver(this);
 }
 
-void CompositorFrameSinkHolder::UpdateNeedsBeginFrame() {
-  if (!begin_frame_source_)
-    return;
-
-  bool needs_begin_frame = surface_ && surface_->NeedsBeginFrame();
-  if (needs_begin_frame == needs_begin_frame_)
-    return;
-
-  needs_begin_frame_ = needs_begin_frame;
-  OnNeedsBeginFrames(needs_begin_frame_);
-}
-
 }  // namespace exo