improvements of the FPS counter in the HUDLayer

cc/heads_up_display_layer_impl.h

Index: cc/heads_up_display_layer_impl.h
diff --git a/cc/heads_up_display_layer_impl.h b/cc/heads_up_display_layer_impl.h
index b17644a38508db3dc3443adfa6a9c9f9d670363a..b4b9d43a6969e54e766214b52e3b9e1dbb0f914f 100644
--- a/cc/heads_up_display_layer_impl.h
+++ b/cc/heads_up_display_layer_impl.h
@@ -6,11 +6,14 @@
 #define CCHeadsUpDisplayLayerImpl_h
 
 #include "base/memory/scoped_ptr.h"
+#include "base/time.h"
 #include "cc/font_atlas.h"
 #include "cc/layer_impl.h"
 #include "cc/scoped_texture.h"
 
 class SkCanvas;
+class SkPaint;
+class SkRect;
 
 namespace cc {
 
@@ -43,13 +46,19 @@ private:
     virtual const char* layerTypeAsString() const OVERRIDE;
 
     void drawHudContents(SkCanvas*);
-    void drawFPSCounter(SkCanvas*, FrameRateCounter*, int top, int height);
-    void drawFPSCounterText(SkCanvas*, FrameRateCounter*, int top, int width, int height);
+    int drawFPSCounter(SkCanvas*, FrameRateCounter*);
+    void drawFPSCounterText(SkCanvas*, SkPaint&, FrameRateCounter*, SkRect);
+    void drawFPSCounterGraph(SkCanvas*, SkPaint&, FrameRateCounter*, SkRect);
     void drawDebugRects(SkCanvas*, DebugRectHistory*);
 
     scoped_ptr<FontAtlas> m_fontAtlas;
     scoped_ptr<ScopedTexture> m_hudTexture;
     scoped_ptr<SkCanvas> m_hudCanvas;
+
+    double m_averageFPS;
+    double m_stdDeviation;
+
+    base::TimeTicks textUpdateTime;
 };
 
 }  // namespace cc