GPU Tracer no longer issue device traces when device category is off.

gpu/command_buffer/service/gpu_tracer.cc

Index: gpu/command_buffer/service/gpu_tracer.cc
diff --git a/gpu/command_buffer/service/gpu_tracer.cc b/gpu/command_buffer/service/gpu_tracer.cc
index a633959f385d11f9ff0ad72f543bc3bd5d2b8543..c38ced703578ec6c9c9bbc7b220852cc65ecc4d1 100644
--- a/gpu/command_buffer/service/gpu_tracer.cc
+++ b/gpu/command_buffer/service/gpu_tracer.cc
@@ -90,7 +90,8 @@ GPUTrace::GPUTrace(scoped_refptr<Outputter> outputter,
       name_(name),
       outputter_(outputter),
       enabled_(enabled) {
-  if (gpu_timing_client->IsAvailable() &&
+  if (enabled &&

[vmiura, 2015/04/10 22:18:50]

Thinking about this, "enabled" here and "tracing_service" in Start() and End()
seem rather inconsistent.

Should we have both 'device_enabled' and 'service_enabled' in the constructor?

[David Yen, 2015/04/10 22:36:09]

Done.

+      gpu_timing_client->IsAvailable() &&
       gpu_timing_client->IsTimerOffsetAvailable()) {
     gpu_timer_ = gpu_timing_client->CreateGPUTimer();
   }