cc: Send all begin frames using a PostTask.

cc/test/scheduler_test_common.h

Index: cc/test/scheduler_test_common.h
diff --git a/cc/test/scheduler_test_common.h b/cc/test/scheduler_test_common.h
index 8bb8a9d565875f8e53dc4b7fba6042c7f01eb7db..aa8a777f993b175a644e4657b29c5fefa49e4173 100644
--- a/cc/test/scheduler_test_common.h
+++ b/cc/test/scheduler_test_common.h
@@ -38,40 +38,6 @@ class FakeDelayBasedTimeSourceClient : public DelayBasedTimeSourceClient {
   DISALLOW_COPY_AND_ASSIGN(FakeDelayBasedTimeSourceClient);
 };
 
-class FakeDelayBasedTimeSource : public DelayBasedTimeSource {
- public:
-  explicit FakeDelayBasedTimeSource(base::SingleThreadTaskRunner* task_runner)
-      : DelayBasedTimeSource(task_runner) {}
-  ~FakeDelayBasedTimeSource() override {}
-
-  void SetNow(base::TimeTicks time) { now_ = time; }
-  base::TimeTicks Now() const override;
-
- protected:
-  base::TimeTicks now_;
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(FakeDelayBasedTimeSource);
-};
-
-class TestDelayBasedTimeSource : public DelayBasedTimeSource {
- public:
-  TestDelayBasedTimeSource(base::SimpleTestTickClock* now_src,
-                           OrderedSimpleTaskRunner* task_runner);
-  ~TestDelayBasedTimeSource() override;
-
- protected:
-  // Overridden from DelayBasedTimeSource
-  base::TimeTicks Now() const override;
-  std::string TypeString() const override;
-
-  // Not owned.
-  base::SimpleTestTickClock* now_src_;
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(TestDelayBasedTimeSource);
-};
-
 class FakeCompositorTimingHistory : public CompositorTimingHistory {
  public:
   static std::unique_ptr<FakeCompositorTimingHistory> Create(