Added GL_CHROMIUM_trace_marker feature as well as gpu_toplevel markers.

base/debug/trace_event.h

 // Copyright (c) 2012 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.
 
 // This header file defines the set of trace_event macros without specifying
 // how the events actually get collected and stored. If you need to expose trace
 // events to some other universe, you can copy-and-paste this file as well as
 // trace_event.h, modifying the macros contained there as necessary for the
 // target platform. The end result is that multiple libraries can funnel events
 // through to a shared trace event collector.
@@ skipping 770 matching lines @@
 
 #define TRACE_EVENT_OBJECT_DELETED_WITH_ID(category_group, name, id) \
     INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_DELETE_OBJECT, \
         category_group, name, TRACE_ID_DONT_MANGLE(id), TRACE_EVENT_FLAG_NONE)
 
 #define INTERNAL_TRACE_EVENT_CATEGORY_GROUP_ENABLED_FOR_RECORDING_MODE() \
     UNLIKELY(*INTERNAL_TRACE_EVENT_UID(category_group_enabled) & \
         (base::debug::TraceLog::ENABLED_FOR_RECORDING | \
          base::debug::TraceLog::ENABLED_FOR_EVENT_CALLBACK))
 
+// Macros to track GPU timings much like the CPU variants.
+#define TRACE_GPU_EVENT_BEGIN0(context, category_group, name) \
+    do { \
+      context->TraceBeginCHROMIUM(category_group, name); \

[vmiura, 2014/12/09 00:18:10]

I think we should check if the category is enabled here, and in the END0.

if (INTERNAL_TRACE_EVENT_CATEGORY_GROUP_ENABLED_FOR_RECORDING_MODE()) {
 ...
}

+    } while (0)
+
+#define TRACE_GPU_EVENT_END0(context) \
+    do { \
+      context->TraceEndCHROMIUM(); \
+    } while (0)
+
 // Macro to efficiently determine if a given category group is enabled.
 #define TRACE_EVENT_CATEGORY_GROUP_ENABLED(category_group, ret) \
     do { \
       INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(category_group); \
       if (INTERNAL_TRACE_EVENT_CATEGORY_GROUP_ENABLED_FOR_RECORDING_MODE()) { \
         *ret = true; \
       } else { \
         *ret = false; \
       } \
     } while (0)
@@ skipping 769 matching lines @@
   const char* name_;
   IDType id_;
 
   DISALLOW_COPY_AND_ASSIGN(TraceScopedTrackableObject);
 };
 
 } // namespace debug
 } // namespace base
 
 #endif /* BASE_DEBUG_TRACE_EVENT_H_ */