[not for review] Add Draw entries to window Performance Timeline

cc/debug/smoothness_timing_tracker.h

Index: cc/debug/smoothness_timing_tracker.h
diff --git a/cc/debug/smoothness_timing_tracker.h b/cc/debug/smoothness_timing_tracker.h
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index 0000000000000000000000000000000000000000..3114a19cf754bdb8aea61e079217cac77ae63ae2
--- /dev/null
+++ b/cc/debug/smoothness_timing_tracker.h
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+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CC_DEBUG_SMOOTHNESS_TIMING_TRACKER_H_
+#define CC_DEBUG_SMOOTHNESS_TIMING_TRACKER_H_
+
+#include <set>
+#include <utility>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/containers/hash_tables.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/time/time.h"
+#include "cc/debug/ring_buffer.h"
+#include "cc/trees/layer_tree_host_common.h"
+
+namespace cc {
+
+// This class maintains a history of timestamps and rect IDs to communicate
+// smoothness events back to Blink
+class SmoothnessTimingTracker {
+ public:
+  struct SmoothnessTimingCompositeEvent {
+    int frame_id_;
+    int64_t rect_id_;
+    base::TimeTicks timestamp_;
+    SmoothnessTimingCompositeEvent(int frame_id,
+                                   int64_t rect_id,
+                                   base::TimeTicks timestamp)
+        : frame_id_(frame_id), rect_id_(rect_id), timestamp_(timestamp) {}
+    SmoothnessTimingCompositeEvent() {}
+    SmoothnessTimingCompositeEvent(const SmoothnessTimingCompositeEvent& rhs)
+        : frame_id_(rhs.frame_id_),
+          rect_id_(rhs.rect_id_),
+          timestamp_(rhs.timestamp_) {}
+    SmoothnessTimingCompositeEvent& operator=(
+        const SmoothnessTimingCompositeEvent& rhs) {
+      frame_id_ = rhs.frame_id_;
+      rect_id_ = rhs.rect_id_;
+      timestamp_ = rhs.timestamp_;
+      return *this;
+    }
+  };
+
+  static scoped_ptr<SmoothnessTimingTracker> Create();
+
+  scoped_ptr<CompositeTimingSet> CalculateCompositeCounts();
+
+  void clear_events() { ring_buffer_.Clear(); }
+
+  int current_frame_number() const { return ring_buffer_.CurrentIndex(); }
+  size_t time_stamp_history_size() const { return ring_buffer_.BufferSize(); }
+
+  void SaveTimeStamps(base::TimeTicks timestamp,
+                      const std::vector<std::pair<int, int64_t> >& frame_ids);
+
+  typedef RingBuffer<struct SmoothnessTimingCompositeEvent, 4096>
+      RingBufferType;
+  RingBufferType::Iterator begin() const { return ring_buffer_.Begin(); }
+  RingBufferType::Iterator end() const { return ring_buffer_.End(); }
+
+ private:
+  SmoothnessTimingTracker();
+
+  RingBufferType ring_buffer_;
+
+  DISALLOW_COPY_AND_ASSIGN(SmoothnessTimingTracker);
+};
+
+}  // namespace cc
+
+#endif  // CC_DEBUG_SMOOTHNESS_TIMING_TRACKER_H_