gfx: Add FrameTime and DisplayTime classes

cc/debug/frame_rate_counter.h

Index: cc/debug/frame_rate_counter.h
diff --git a/cc/debug/frame_rate_counter.h b/cc/debug/frame_rate_counter.h
index 0b69b29aea541be345102d281c1acbf130fa7a79..ce6bd4a28a62071a848ec878ed9eff34f7956c59 100644
--- a/cc/debug/frame_rate_counter.h
+++ b/cc/debug/frame_rate_counter.h
@@ -9,6 +9,7 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/time/time.h"
 #include "cc/debug/ring_buffer.h"
+#include "ui/gfx/frame_time.h"
 
 namespace cc {
 
@@ -22,7 +23,7 @@ class FrameRateCounter {
   int dropped_frame_count() const { return dropped_frame_count_; }
   size_t time_stamp_history_size() const { return ring_buffer_.BufferSize(); }
 
-  void SaveTimeStamp(base::TimeTicks timestamp, bool software);
+  void SaveTimeStamp(gfx::FrameTime timestamp, bool software);
 
   // n = 0 returns the oldest frame interval retained in the history, while n =
   // time_stamp_history_size() - 1 returns the most recent frame interval.
@@ -37,7 +38,7 @@ class FrameRateCounter {
   void GetMinAndMaxFPS(double* min_fps, double* max_fps) const;
   double GetAverageFPS() const;
 
-  typedef RingBuffer<base::TimeTicks, 136> RingBufferType;
+  typedef RingBuffer<gfx::FrameTime, 136> RingBufferType;
   RingBufferType::Iterator begin() const { return ring_buffer_.Begin(); }
   RingBufferType::Iterator end() const { return ring_buffer_.End(); }