cc: Heuristic for Renderer latency recovery

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 cf29ca9b6a53ec89a43c1b20e905e9c4792dff8f..514d11eb638abf1dede161c68e799e59a2249511 100644
--- a/cc/scheduler/scheduler_state_machine.h
+++ b/cc/scheduler/scheduler_state_machine.h
@@ -126,6 +126,10 @@ class CC_EXPORT SchedulerStateMachine {
   // to make progress.
   bool BeginFrameNeeded() const;
 
+  // Notifies the state machine that the Scheduler skipped a BeginImplFrame
+  // so the state machine can reset associated state.
+  void DidSkipBeginImplFrameToReduceLatency();
+
   // Indicates that the system has entered and left a BeginImplFrame callback.
   // The scheduler will not draw more than once in a given BeginImplFrame
   // callback nor send more than one BeginMainFrame message.
@@ -145,6 +149,10 @@ class CC_EXPORT SchedulerStateMachine {
   // impl thread to draw, it is in a high latency mode.
   bool MainThreadIsInHighLatencyMode() const;
 
+  bool swaps_are_likely_high_latency() const {
+    return swaps_are_likely_high_latency_;
+  }
+
   // Indicates whether the LayerTreeHostImpl is visible.
   void SetVisible(bool visible);
   bool visible() const { return visible_; }
@@ -193,6 +201,7 @@ class CC_EXPORT SchedulerStateMachine {
   // updates from the main thread to the impl, or to push deltas from the impl
   // thread to main.
   void SetNeedsCommit();
+  bool NeedsCommitForTesting() const { return needs_commit_; }

[sunnyps, 2015/05/12 00:36:25]

nit: This could be renamed to needs_commit. That way it follows the naming
convention for inline methods. Given that this is a const accessor I see no harm
in exposing this.

[brianderson, 2015/05/12 19:25:17]

Done.

 
   // Call this only in response to receiving an ACTION_SEND_BEGIN_MAIN_FRAME
   // from NextAction.
@@ -317,6 +326,8 @@ class CC_EXPORT SchedulerStateMachine {
   int consecutive_checkerboard_animations_;
   int max_pending_swaps_;
   int pending_swaps_;
+  bool swaps_are_likely_high_latency_;
+  bool swap_throttled_in_last_deadline_;
   bool needs_redraw_;
   bool needs_animate_;
   bool needs_prepare_tiles_;