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 began compositing
+  INPUT_EVENT_BROWSER_COMPOSITE_COMPONENT,

[jbauman, 2014/09/19 20:40:29]

These don't really have anything to do with input events, so I don't think we
should have INPUT_EVENT in the name.

[orglofch, 2014/09/19 22:40:27]

Technically the events are still tied to input in that latency_info only has
input related begin components. I was planning on renaming these in a later
patch once I've added per frame latency_info.

+  // Timestamp of when an unparented output surface began swap buffers

[brianderson, 2014/09/18 23:26:15]

"an uparented output surface" -> "the Browser process"

[orglofch, 2014/09/19 22:40:27]

Done.

+  INPUT_EVENT_OUTPUT_SURFACE_SWAP_BUFFER_COMPONENT,

[brianderson, 2014/09/18 23:26:15]

INPUT_EVENT_BROWSER_SWAP_BUFFER_COMPONENT?

[orglofch, 2014/09/19 22:40:27]

Done.

+  // 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 88 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_