cc: add DevTools instrumentation for impl-side frames

cc/debug/devtools_instrumentation.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 CC_DEBUG_DEVTOOLS_INSTRUMENTATION_H_
 #define CC_DEBUG_DEVTOOLS_INSTRUMENTATION_H_
 
 #include "base/debug/trace_event.h"
 
 namespace cc {
 namespace devtools_instrumentation {
 
 namespace internal {
 const char kCategory[] = "cc,devtools";
+const char kFrameId[] = "frameId";
 const char kLayerId[] = "layerId";
 const char kLayerTreeId[] = "layerTreeId";
 const char kPixelRefId[] = "pixelRefId";
 
 const char kImageDecodeTask[] = "ImageDecodeTask";
-}
+const char kBeginFrame[] = "BeginFrame";
+const char kCommitMainThreadFrame[] = "CommitMainThreadFrame";
+}  // namespace internal
 
 const char kPaintLayer[] = "PaintLayer";
 const char kRasterTask[] = "RasterTask";
 const char kPaintSetup[] = "PaintSetup";
 const char kUpdateLayer[] = "UpdateLayer";
 
 class ScopedLayerTask {
  public:
   ScopedLayerTask(const char* event_name, int layer_id)
     : event_name_(event_name) {
@@ skipping 46 matching lines @@
       : base::debug::TraceScopedTrackableObject<int>(
             internal::kCategory,
             internal::kLayerId,
             layer_id) {
   }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ScopedLayerObjectTracker);
 };
 
+inline void didCommitMainThreadFrame(uint64 tree_id, int frame_id) {

[nduca, 2013/11/12 05:51:18]

oh i get it now, i gave you bad advice...

you want to call these layer_tree_host_id ... tree ids are actually a group of
layers, they are actually different from the hosts.

+  TRACE_EVENT_INSTANT2(internal::kCategory,
+                       internal::kCommitMainThreadFrame,
+                       TRACE_EVENT_SCOPE_THREAD,
+                       internal::kLayerTreeId, tree_id,
+                       internal::kFrameId, frame_id);
+}
+
+inline void didBeginFrame(uint64 tree_id) {
+  TRACE_EVENT_INSTANT1(internal::kCategory,
+                       internal::kBeginFrame,
+                       TRACE_EVENT_SCOPE_THREAD,
+                       internal::kLayerTreeId, tree_id);

[nduca, 2013/11/12 05:51:18]

would it be better to include the frame id on this? i assume you're going to use
wall time to sort out the mapping but i think we know it so we could just
include it every time?

+}
+
 }  // namespace devtools_instrumentation
 }  // namespace cc
 
 #endif  // CC_DEBUG_DEVTOOLS_INSTRUMENTATION_H_