Add new latency_info for tracking browser composite time.

ui/events/latency_info.h

 // Copyright 2013 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 UI_EVENTS_LATENCY_INFO_H_
 #define UI_EVENTS_LATENCY_INFO_H_
 
 #include <utility>
 #include <vector>
 
@@ skipping 36 matching lines @@
   INPUT_EVENT_LATENCY_ACKED_TOUCH_COMPONENT,
   // Frame number when a window snapshot was requested. The snapshot
   // is taken when the rendering results actually reach the screen.
   WINDOW_SNAPSHOT_FRAME_NUMBER_COMPONENT,
   // Frame number for a snapshot requested via
   // gpuBenchmarking.beginWindowSnapshotPNG
   // TODO(vkuzkokov): remove when patch adding this hits Stable
   WINDOW_OLD_SNAPSHOT_FRAME_NUMBER_COMPONENT,
   // Timestamp when a tab is requested to be shown.
   TAB_SHOW_COMPONENT,
+  // Timestamp of when the Browser process began compositing
+  INPUT_EVENT_RENDERER_SWAP_RECEIVED_COMPONENT,
+  // Timestamp of when the Browser process began swap buffers
+  INPUT_EVENT_BROWSER_SWAP_BUFFER_COMPONENT,
+  // Timestamp of when the gpu service began swap buffers, unlike
+  // INPUT_EVENT_LATENCY_TERMINATED_FRAME_SWAP_COMPONENT which measure after
+  INPUT_EVENT_GPU_SWAP_BUFFER_COMPONENT,
   // ---------------------------TERMINAL COMPONENT-----------------------------
   // TERMINAL COMPONENT is when we show the latency end in chrome://tracing.
   // Timestamp when the mouse event is acked from renderer and it does not
   // cause any rendering scheduled.
   INPUT_EVENT_LATENCY_TERMINATED_MOUSE_COMPONENT,
   // Timestamp when the touch event is acked from renderer and it does not
   // cause any rendering schedueld and does not generate any gesture event.
   INPUT_EVENT_LATENCY_TERMINATED_TOUCH_COMPONENT,
   // Timestamp when the gesture event is acked from renderer, and it does not
   // cause any rendering schedueld.
@@ skipping 21 matching lines @@
     // Nondecreasing number that can be used to determine what events happened
     // in the component at the time this struct was sent on to the next
     // component.
     int64 sequence_number;
     // Average time of events that happened in this component.
     base::TimeTicks event_time;
     // Count of events that happened in this component
     uint32 event_count;
   };
 
   // Empirically determined constant based on a typical scroll sequence.

[Yufeng Shen (Slow to review), 2014/10/01 21:46:19]

Can you tune this number ?

[orglofch, 2014/10/02 00:46:04]

Yep, I've made it 9 since all 3 of the new components will be added when we
don't abort a commit.

   enum { kTypicalMaxComponentsPerLatencyInfo = 6 };
 
   // Map a Latency Component (with a component-specific int64 id) to a
   // component info.
   typedef base::SmallMap<
       std::map<std::pair<LatencyComponentType, int64>, LatencyComponent>,
       kTypicalMaxComponentsPerLatencyInfo> LatencyMap;
 
   LatencyInfo();
 
@@ skipping 46 matching lines @@
   LatencyMap latency_components;
   // The unique id for matching the ASYNC_BEGIN/END trace event.
   int64 trace_id;
   // Whether a terminal component has been added.
   bool terminated;
 };
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_LATENCY_INFO_H_