Add BeginFrameObserverProxy

cc/scheduler/scheduler_unittest.cc

Index: cc/scheduler/scheduler_unittest.cc
diff --git a/cc/scheduler/scheduler_unittest.cc b/cc/scheduler/scheduler_unittest.cc
index 9346536e9344e965d1422f7202af9cd0c2753ea9..0a49346602b17c5b7ac1f9448bf8eaa852b96048 100644
--- a/cc/scheduler/scheduler_unittest.cc
+++ b/cc/scheduler/scheduler_unittest.cc
@@ -407,7 +407,6 @@ TEST_F(SchedulerTest, InitializeOutputSurfaceDoesNotBeginImplFrame) {
 
 TEST_F(SchedulerTest, SendBeginFramesToChildren) {
   scheduler_settings_.use_external_begin_frame_source = true;
-  scheduler_settings_.forward_begin_frames_to_children = true;
   SetUpScheduler(true);
 
   EXPECT_FALSE(client_->begin_frame_is_sent_to_children());
@@ -428,7 +427,6 @@ TEST_F(SchedulerTest, SendBeginFramesToChildren) {
 
 TEST_F(SchedulerTest, SendBeginFramesToChildrenWithoutCommit) {
   scheduler_settings_.use_external_begin_frame_source = true;
-  scheduler_settings_.forward_begin_frames_to_children = true;
   SetUpScheduler(true);
 
   EXPECT_FALSE(client_->needs_begin_frames());