Revert of cc: Adding DidFinishImplFrame to LTHI.

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index eea6236ab6280627eba8b0e6a3e251c90781b26d..1c602b9b944708a3d63a9f83262bc2814f1f16b0 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -1671,12 +1671,7 @@
 void LayerTreeHostImpl::WillBeginImplFrame(const BeginFrameArgs& args) {
   // Sample the frame time now. This time will be used for updating animations
   // when we draw.
-  DCHECK(!current_begin_frame_args_.IsValid());
-  current_begin_frame_args_ = args;
-  // TODO(mithro): Stop overriding the frame time once the usage of frame
-  // timing is unified.
-  current_begin_frame_args_.frame_time = gfx::FrameTime::Now();
-
+  UpdateCurrentBeginFrameArgs(args);
   // Cache the begin impl frame interval
   begin_impl_frame_interval_ = args.interval;
 
@@ -1689,11 +1684,6 @@
 
   for (auto& it : video_frame_controllers_)
     it->OnBeginFrame(args);
-}
-
-void LayerTreeHostImpl::DidFinishImplFrame() {
-  DCHECK(current_begin_frame_args_.IsValid());
-  current_begin_frame_args_ = BeginFrameArgs();
 }
 
 void LayerTreeHostImpl::UpdateViewportContainerSizes() {
@@ -3143,6 +3133,19 @@
   return global_tile_state_.tree_priority;
 }
 
+void LayerTreeHostImpl::UpdateCurrentBeginFrameArgs(
+    const BeginFrameArgs& args) {
+  DCHECK(!current_begin_frame_args_.IsValid());
+  current_begin_frame_args_ = args;
+  // TODO(skyostil): Stop overriding the frame time once the usage of frame
+  // timing is unified.
+  current_begin_frame_args_.frame_time = gfx::FrameTime::Now();
+}
+
+void LayerTreeHostImpl::ResetCurrentBeginFrameArgsForNextFrame() {
+  current_begin_frame_args_ = BeginFrameArgs();
+}
+
 BeginFrameArgs LayerTreeHostImpl::CurrentBeginFrameArgs() const {
   // Try to use the current frame time to keep animations non-jittery.  But if
   // we're not in a frame (because this is during an input event or a delayed