gpu: Early return GpuCommandBufferStub::OnWaitSyncPoint() if the sync point is retired.

content/common/gpu/gpu_command_buffer_stub.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 "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/hash.h"
 #include "base/memory/shared_memory.h"
@@ skipping 750 matching lines @@
 }
 
 void GpuCommandBufferStub::OnRetireSyncPoint(uint32 sync_point) {
   DCHECK(!sync_points_.empty() && sync_points_.front() == sync_point);
   sync_points_.pop_front();
   GpuChannelManager* manager = channel_->gpu_channel_manager();
   manager->sync_point_manager()->RetireSyncPoint(sync_point);
 }
 
 bool GpuCommandBufferStub::OnWaitSyncPoint(uint32 sync_point) {
+  GpuChannelManager* manager = channel_->gpu_channel_manager();
+  if (manager->sync_point_manager()->IsSyncPointRetired(sync_point))
+    return true;
+
   if (sync_point_wait_count_ == 0) {
     TRACE_EVENT_ASYNC_BEGIN1("gpu", "WaitSyncPoint", this,
                              "GpuCommandBufferStub", this);
   }
   scheduler_->SetScheduled(false);
   ++sync_point_wait_count_;
-  GpuChannelManager* manager = channel_->gpu_channel_manager();
   manager->sync_point_manager()->AddSyncPointCallback(
       sync_point,
       base::Bind(&GpuCommandBufferStub::OnSyncPointRetired,
                  this->AsWeakPtr()));
   return scheduler_->IsScheduled();
 }
 
 void GpuCommandBufferStub::OnSyncPointRetired() {
   --sync_point_wait_count_;
   if (sync_point_wait_count_ == 0) {
@@ skipping 173 matching lines @@
   if (decoder_)
     decoder_->LoseContext(GL_UNKNOWN_CONTEXT_RESET_ARB);
   command_buffer_->SetParseError(gpu::error::kLostContext);
 }
 
 uint64 GpuCommandBufferStub::GetMemoryUsage() const {
   return GetMemoryManager()->GetClientMemoryUsage(this);
 }
 
 }  // namespace content