cc: Add scheduler support for invalidating content on impl thread.

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 3272588d56894ee6b27ef4fd2977109052bbba27..2de0df3f05e1720e621beac414086a07bed723a3 100644
--- a/cc/scheduler/scheduler_state_machine.h
+++ b/cc/scheduler/scheduler_state_machine.h
@@ -115,6 +115,7 @@ class CC_EXPORT SchedulerStateMachine {
     ACTION_SEND_BEGIN_MAIN_FRAME,
     ACTION_COMMIT,
     ACTION_ACTIVATE_SYNC_TREE,
+    ACTION_RUN_IMPL_SIDE_INVALIDATION,
     ACTION_DRAW_IF_POSSIBLE,
     ACTION_DRAW_FORCED,
     ACTION_DRAW_ABORT,
@@ -249,6 +250,9 @@ class CC_EXPORT SchedulerStateMachine {
   // Indicates the active tree's visible tiles are ready to be drawn.
   void NotifyReadyToDraw();
 
+  void SetNeedsImplSideInvalidation();
+  void WillRunImplSideInvalidation();
+
   bool has_pending_tree() const { return has_pending_tree_; }
   bool active_tree_needs_first_draw() const {
     return active_tree_needs_first_draw_;
@@ -276,6 +280,9 @@ class CC_EXPORT SchedulerStateMachine {
   bool BeginFrameNeededForVideo() const;
   bool ProactiveBeginFrameWanted() const;
 
+  bool ShouldRunImplSideInvalidation() const;
+  bool CouldCreatePendingTree() const;
+
   bool ShouldTriggerBeginImplFrameDeadlineImmediately() const;
 
   // True if we need to force activations to make forward progress.
@@ -313,6 +320,7 @@ class CC_EXPORT SchedulerStateMachine {
   bool draw_funnel_;
   bool send_begin_main_frame_funnel_;
   bool invalidate_compositor_frame_sink_funnel_;
+  bool impl_side_invalidation_funnel_;
   // prepare_tiles_funnel_ is "filled" each time PrepareTiles is called
   // and "drained" on each BeginImplFrame. If the funnel gets too full,
   // we start throttling ACTION_PREPARE_TILES such that we average one
@@ -345,6 +353,8 @@ class CC_EXPORT SchedulerStateMachine {
   bool wait_for_ready_to_draw_;
   bool did_draw_in_last_frame_;
   bool did_submit_in_last_frame_;
+  bool needs_impl_side_invalidation_;
+  bool run_impl_side_invalidation_after_main_frame_aborted_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SchedulerStateMachine);