WebGraphicsContext3DCommandBufferImpl cleanup, Canvas2D thottling fix, GpuScheduler fix.

gpu/command_buffer/service/gpu_scheduler.h

 // Copyright (c) 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.
 
 #ifndef GPU_COMMAND_BUFFER_SERVICE_GPU_SCHEDULER_H_
 #define GPU_COMMAND_BUFFER_SERVICE_GPU_SCHEDULER_H_
 
 #include <queue>
 #include <vector>
 
@@ skipping 21 matching lines @@
 
 namespace gpu {
 namespace gles2 {
 class ContextGroup;
 }
 
 // This class processes commands in a command buffer. It is event driven and
 // posts tasks to the current message loop to do additional work.
 class GpuScheduler : public CommandBufferEngine {
  public:
+  // Scheduler quantum: makes ProcessCommands continue until the specified time
+  // has passed, or the command buffer yields or runs out of commands.
+  static const int kMinimumSchedulerQuantumMicros = 2000;
+
   // If a group is not passed in one will be created.
   GpuScheduler(CommandBuffer* command_buffer,
                SurfaceManager* surface_manager,
                gles2::ContextGroup* group);
 
   // This constructor is for unit tests.
   GpuScheduler(CommandBuffer* command_buffer,
                gles2::GLES2Decoder* decoder,
                CommandParser* parser,
                int commands_per_update);
@@ skipping 130 matching lines @@
 #endif
 
   ScopedRunnableMethodFactory<GpuScheduler> method_factory_;
   scoped_ptr<Callback0::Type> wrapped_swap_buffers_callback_;
   scoped_ptr<Callback0::Type> command_processed_callback_;
 };
 
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_GPU_SCHEDULER_H_