WebGraphicsContext3DCommandBufferImpl cleanup, Canvas2D thottling fix, GpuScheduler fix.

gpu/command_buffer/service/mocks.h

Index: gpu/command_buffer/service/mocks.h
diff --git a/gpu/command_buffer/service/mocks.h b/gpu/command_buffer/service/mocks.h
index 0d341bddfcc40c7b39ae1e200eb01f24fbcb3420..edbedb26ae84d2a5a76966797148131bb27ee56d 100644
--- a/gpu/command_buffer/service/mocks.h
+++ b/gpu/command_buffer/service/mocks.h
@@ -69,6 +69,20 @@ class AsyncAPIMock : public AsyncAPIInterface {
   CommandBufferEngine *engine_;
 };
 
+// Allows specialized behavior per command in DoCommand.
+class SpecializedAsyncAPIMock : public AsyncAPIMock {
+ public:
+  // Cause DoCommand to sleep more than the GpuScheduler time quantum.
+  static const unsigned int kTestQuantumCommand = 333;
+
+  SpecializedAsyncAPIMock();
+  virtual ~SpecializedAsyncAPIMock();
+
+  virtual error::Error DoCommand(unsigned int command,
+                                 unsigned int arg_count,
+                                 const void* cmd_data);
+};
+
 namespace gles2 {
 
 class MockShaderTranslator : public ShaderTranslatorInterface {