cc: Improve frame/commit accounting

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 3196c28008b4920d0a0d241c4e4a3ac950e0fa40..eb337c3e16c7267f4004476ff199736235578239 100644
--- a/cc/frame_rate_counter.h
+++ b/cc/frame_rate_counter.h
@@ -5,6 +5,7 @@
 #ifndef CCFrameRateCounter_h
 #define CCFrameRateCounter_h
 
+#include "CCRenderingStats.h"
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time.h"
@@ -17,9 +18,11 @@ class CCFrameRateCounter {
 public:
     static scoped_ptr<CCFrameRateCounter> create();
 
+    void setTimebaseAndInterval(base::TimeTicks timebase, base::TimeDelta interval);
+
     void markBeginningOfFrame(base::TimeTicks timestamp);
     void markEndOfFrame();
-    int currentFrameNumber() const { return m_currentFrameNumber; }
+    int64_t currentFrameNumber() const { return m_currentFrameNumber; }
     void getAverageFPSAndStandardDeviation(double& averageFPS, double& standardDeviation) const;
     int timeStampHistorySize() const { return kTimeStampHistorySize; }
 
@@ -31,7 +34,7 @@ public:
     // true if the given frame interval is too fast or too slow, based on constant thresholds.
     bool isBadFrameInterval(base::TimeDelta intervalBetweenConsecutiveFrames) const;
 
-    int droppedFrameCount() const { return m_droppedFrameCount; }
+    void renderingStats(CCRenderingStats* stats) const;
 
 private:
     CCFrameRateCounter();
@@ -39,24 +42,24 @@ private:
     base::TimeDelta frameInterval(int frameNumber) const;
     int frameIndex(int frameNumber) const;
     bool isBadFrame(int frameNumber) const;
-
-    // Two thresholds (measured in seconds) that describe what is considered to be a "no-op frame" that should not be counted.
-    // - if the frame is too fast, then given our compositor implementation, the frame probably was a no-op and did not draw.
-    // - if the frame is too slow, then there is probably not animating content, so we should not pollute the average.
-    static const double kFrameTooFast;
-    static const double kFrameTooSlow;
-
-    // If a frame takes longer than this threshold (measured in seconds) then we
-    // (naively) assume that it missed a screen refresh; that is, we dropped a frame.
-    // FIXME: Determine this threshold based on monitor refresh rate, crbug.com/138642.
-    static const double kDroppedFrameTime;
+    int64_t currentVsyncCount(base::TimeTicks now) const;
 
     static const int kTimeStampHistorySize = 120;
 
-    int m_currentFrameNumber;
     base::TimeTicks m_timeStampHistory[kTimeStampHistorySize];
 
-    int m_droppedFrameCount;
+    // Two thresholds (measured in seconds) that describe what is considered to be a "no-op frame" that should not be counted.
+    // - if the frame is too fast, then given our compositor implementation, the frame probably was a no-op and did not draw.
+    // - if the frame is too slow, then there is probably not animating content, so we should not pollute the average.
+    double m_frameTooFastSeconds;
+    double m_frameTooSlowSeconds;
+
+    int64_t m_vsyncCount;
+    int64_t m_currentFrameNumber;
+    bool m_active;
+    base::TimeTicks m_activeTimestamp;
+    base::TimeTicks m_intervalChangedTime;
+    base::TimeDelta m_interval;
 
     DISALLOW_COPY_AND_ASSIGN(CCFrameRateCounter);
 };