Remove CompositorObserver::OnCompositingEnded()

ui/compositor/compositor.cc

 // Copyright (c) 2012 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 "ui/compositor/compositor.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <deque>
@@ skipping 507 matching lines @@
 
 void Compositor::DidFailToInitializeCompositorFrameSink() {
   // The CompositorFrameSink should already be bound/initialized before being
   // given to
   // the Compositor.
   NOTREACHED();
 }
 
 void Compositor::DidCommit() {
   DCHECK(!IsLocked());
+  ++committed_frame_number_;
   for (auto& observer : observer_list_)
     observer.OnCompositingDidCommit(this);
 }
 
-void Compositor::DidReceiveCompositorFrameAck() {
-  ++committed_frame_number_;
-  for (auto& observer : observer_list_)
-    observer.OnCompositingEnded(this);
-}
+void Compositor::DidReceiveCompositorFrameAck() {}
 
 void Compositor::DidSubmitCompositorFrame() {
   base::TimeTicks start_time = base::TimeTicks::Now();
   for (auto& observer : observer_list_)
     observer.OnCompositingStarted(this, start_time);
 }
 
 void Compositor::SetOutputIsSecure(bool output_is_secure) {
   if (context_factory_private_)
     context_factory_private_->SetOutputIsSecure(this, output_is_secure);
@@ skipping 29 matching lines @@
   for (auto& observer : observer_list_)
     observer.OnCompositingLockStateChanged(this);
 }
 
 void Compositor::CancelCompositorLock() {
   if (compositor_lock_)
     compositor_lock_->CancelLock();
 }
 
 }  // namespace ui