Revert of cc: Adding BeginFrameTracker object and removing Now() from LTHI.

cc/trees/layer_tree_host_impl_unittest.cc

Index: cc/trees/layer_tree_host_impl_unittest.cc
diff --git a/cc/trees/layer_tree_host_impl_unittest.cc b/cc/trees/layer_tree_host_impl_unittest.cc
index 86c33e002903cf14894f53e02aa62f2159bd17e0..c4fd648678d1fdb0d1a9089fc7942d17c313b835 100644
--- a/cc/trees/layer_tree_host_impl_unittest.cc
+++ b/cc/trees/layer_tree_host_impl_unittest.cc
@@ -180,9 +180,6 @@
         task_graph_runner_.get(), 0);
     bool init = host_impl_->InitializeRenderer(output_surface.Pass());
     host_impl_->SetViewportSize(gfx::Size(10, 10));
-    // Set the BeginFrameArgs so that methods which use it are able to.
-    host_impl_->WillBeginImplFrame(
-        CreateBeginFrameArgsForTesting(BEGINFRAME_FROM_HERE));
     return init;
   }
 
@@ -5053,8 +5050,6 @@
           settings, this, &proxy_, &stats_instrumentation_,
           shared_bitmap_manager_.get(), NULL, task_graph_runner_.get(), 0);
   layer_tree_host_impl->InitializeRenderer(output_surface.Pass());
-  layer_tree_host_impl->WillBeginImplFrame(
-      CreateBeginFrameArgsForTesting(BEGINFRAME_FROM_HERE));
   layer_tree_host_impl->SetViewportSize(gfx::Size(500, 500));
 
   scoped_ptr<LayerImpl> root =
@@ -5343,8 +5338,6 @@
   scoped_ptr<LayerTreeHostImpl> my_host_impl = LayerTreeHostImpl::Create(
       settings, client, proxy, stats_instrumentation, manager, NULL, NULL, 0);
   my_host_impl->InitializeRenderer(output_surface.Pass());
-  my_host_impl->WillBeginImplFrame(
-      CreateBeginFrameArgsForTesting(BEGINFRAME_FROM_HERE));
   my_host_impl->SetViewportSize(gfx::Size(100, 100));
 
   /*
@@ -7663,8 +7656,6 @@
 };
 
 TEST_F(LayerTreeHostImplTest, AddVideoFrameControllerInsideFrame) {
-  host_impl_->DidFinishImplFrame();
-
   BeginFrameArgs begin_frame_args =
       CreateBeginFrameArgsForTesting(BEGINFRAME_FROM_HERE);
   FakeVideoFrameController controller;
@@ -7677,8 +7668,6 @@
 }
 
 TEST_F(LayerTreeHostImplTest, AddVideoFrameControllerOutsideFrame) {
-  host_impl_->DidFinishImplFrame();
-
   BeginFrameArgs begin_frame_args =
       CreateBeginFrameArgsForTesting(BEGINFRAME_FROM_HERE);
   FakeVideoFrameController controller;