[Try # 3] Scheduler refactoring to virtually eliminate redundant DoWorks

cc/scheduler/begin_frame_source_unittest.cc

 // Copyright 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.
 
 #include "cc/scheduler/begin_frame_source.h"
 
 #include <stdint.h>
 
 #include "base/memory/ptr_util.h"
 #include "base/test/test_simple_task_runner.h"
@@ skipping 72 matching lines @@
        RemoveObserverThenDidFinishFrameProducesNoFrame) {
   EXPECT_BEGIN_FRAME_SOURCE_PAUSED(*obs_, false);
   source_->AddObserver(obs_.get());
   EXPECT_BEGIN_FRAME_USED(*obs_, 1000, 1000 + kDeadline, kInterval);
   task_runner_->RunPendingTasks();
 
   now_src_->Advance(base::TimeDelta::FromMicroseconds(100));
   source_->DidFinishFrame(obs_.get(), 0);
   source_->RemoveObserver(obs_.get());
 
-  EXPECT_TRUE(task_runner_->HasPendingTasks());
-  task_runner_->RunPendingTasks();
+  // There was a task posed but it's canceled.

[Sami, 2016/12/09 11:04:02]

typo: posted

[alex clarke (OOO till 29th), 2016/12/12 11:45:04]

I found a way to remove this change.

+  EXPECT_FALSE(task_runner_->HasPendingTasks());
 }
 
 TEST_F(BackToBackBeginFrameSourceTest,
        TogglingObserverThenDidFinishFrameProducesCorrectFrame) {
   EXPECT_BEGIN_FRAME_SOURCE_PAUSED(*obs_, false);
   source_->AddObserver(obs_.get());
   EXPECT_BEGIN_FRAME_USED(*obs_, 1000, 1000 + kDeadline, kInterval);
   task_runner_->RunPendingTasks();
 
   now_src_->Advance(base::TimeDelta::FromMicroseconds(100));
@@ skipping 388 matching lines @@
                                    base::TimeDelta::FromInternalValue(10000));
   now_src_->Advance(base::TimeDelta::FromInternalValue(5000));
   EXPECT_BEGIN_FRAME_SOURCE_PAUSED(obs, false);
   EXPECT_BEGIN_FRAME_USED_MISSED(obs, 10000, 20000, 10000);
   source_->AddObserver(&obs);
   source_->RemoveObserver(&obs);
 }
 
 }  // namespace
 }  // namespace cc