improvements of the FPS counter in the HUDLayer

cc/frame_rate_counter.h

Index: cc/frame_rate_counter.h
diff --git a/cc/frame_rate_counter.h b/cc/frame_rate_counter.h
index 008c2f30e5551f3de73e21506c3fefb3429d5e5d..c6e5fe29da83fa4738f80e54208a14e33e0c337d 100644
--- a/cc/frame_rate_counter.h
+++ b/cc/frame_rate_counter.h
@@ -25,7 +25,7 @@ public:
 
     // n = 0 returns the oldest frame retained in the history,
     // while n = timeStampHistorySize() - 1 returns the timestamp most recent frame.
-    base::TimeTicks timeStampOfRecentFrame(int n);
+    base::TimeTicks timeStampOfRecentFrame(int n) const;
 
     // This is a heuristic that can be used to ignore frames in a reasonable way. Returns
     // true if the given frame interval is too fast or too slow, based on constant thresholds.
@@ -51,7 +51,7 @@ private:
     // FIXME: Determine this threshold based on monitor refresh rate, crbug.com/138642.
     static const double kDroppedFrameTime;
 
-    static const int kTimeStampHistorySize = 120;
+    static const int kTimeStampHistorySize = 170;

[egraether, 2012/10/26 00:06:52]

I increased the number of samples in the graph so the text fits above the graph.

 
     int m_currentFrameNumber;
     base::TimeTicks m_timeStampHistory[kTimeStampHistorySize];