cc: Split animating and drawing into separate actions

cc/scheduler/scheduler_state_machine.h

Index: cc/scheduler/scheduler_state_machine.h
diff --git a/cc/scheduler/scheduler_state_machine.h b/cc/scheduler/scheduler_state_machine.h
index 40a054f119ba50154ec4d08a6bfc175342bdc535..8bec14dbe0899b59d52700e5110bff38247daab9 100644
--- a/cc/scheduler/scheduler_state_machine.h
+++ b/cc/scheduler/scheduler_state_machine.h
@@ -108,6 +108,7 @@ class CC_EXPORT SchedulerStateMachine {
 
   enum Action {
     ACTION_NONE,
+    ACTION_ANIMATE,
     ACTION_SEND_BEGIN_MAIN_FRAME,
     ACTION_COMMIT,
     ACTION_UPDATE_VISIBLE_TILES,
@@ -254,6 +255,7 @@ class CC_EXPORT SchedulerStateMachine {
   // True if we need to force activations to make forward progress.
   bool PendingActivationsShouldBeForced() const;
 
+  bool ShouldAnimate() const;
   bool ShouldBeginOutputSurfaceCreation() const;
   bool ShouldDrawForced() const;
   bool ShouldDraw() const;
@@ -288,6 +290,7 @@ class CC_EXPORT SchedulerStateMachine {
 
   int commit_count_;
   int current_frame_number_;
+  int last_frame_number_animate_performed_;
   int last_frame_number_swap_performed_;
   int last_frame_number_begin_main_frame_sent_;
   int last_frame_number_update_visible_tiles_was_called_;