Merge Group Markers into Chromium Traces.

gpu/command_buffer/service/gles2_cmd_decoder.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index 884566d142471f079e231acac8a0935f632c1a3f..715f7eead480c2a6ea24a75256783670ef4efc1e 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -12411,13 +12411,10 @@ void GLES2DecoderImpl::DoPushGroupMarkerEXT(
   }
   std::string name = length ? std::string(marker, length) : std::string(marker);
   debug_marker_manager_.PushGroup(name);
-  gpu_tracer_->Begin(TRACE_DISABLED_BY_DEFAULT("gpu_group_marker"), name,
-                     kTraceGroupMarker);

[vmiura, 2015/05/12 21:47:42]

Skia currently uses PushGroupMarker / PopGroupMarker.  I'm OK with removing this
once Skia updates to using TraceCHROMIUM.

 }
 
 void GLES2DecoderImpl::DoPopGroupMarkerEXT(void) {
   debug_marker_manager_.PopGroup();
-  gpu_tracer_->End(kTraceGroupMarker);
 }
 
 void GLES2DecoderImpl::DoBindTexImage2DCHROMIUM(