WebGraphicsContext3DCommandBufferImpl cleanup, Canvas2D thottling fix, GpuScheduler fix.

gpu/command_buffer/service/mocks.cc

Index: gpu/command_buffer/service/mocks.cc
diff --git a/gpu/command_buffer/service/mocks.cc b/gpu/command_buffer/service/mocks.cc
index 40b3d6d924fd06e78b4753640724ebdc244e5997..14906c5d44d726fb9d854250e977174d85030821 100644
--- a/gpu/command_buffer/service/mocks.cc
+++ b/gpu/command_buffer/service/mocks.cc
@@ -2,6 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "base/threading/thread.h"
+#include "base/time.h"
+#include "gpu/command_buffer/service/gpu_scheduler.h"
 #include "gpu/command_buffer/service/mocks.h"
 
 namespace gpu {
@@ -24,6 +27,24 @@ void AsyncAPIMock::SetToken(unsigned int command,
   engine_->set_token(args->token);
 }
 
+SpecializedAsyncAPIMock::SpecializedAsyncAPIMock() {}
+
+SpecializedAsyncAPIMock::~SpecializedAsyncAPIMock() {}
+
+error::Error SpecializedAsyncAPIMock::DoCommand(unsigned int command,
+                                                unsigned int arg_count,
+                                                const void* cmd_data) {
+  if (command == kTestQuantumCommand) {
+    // Surpass the GpuScheduler scheduling quantum.
+    base::TimeTicks start_time = base::TimeTicks::Now();
+    while ((base::TimeTicks::Now() - start_time).InMicroseconds() <
+           GpuScheduler::kMinimumSchedulerQuantumMicros) {
+      base::PlatformThread::Sleep(1);
+    }
+  }
+  return AsyncAPIMock::DoCommand(command, arg_count, cmd_data);
+}
+
 namespace gles2 {
 
 MockShaderTranslator::MockShaderTranslator() {}