gpu: Extract the gpu timing code from gpu_tracer.

gpu/command_buffer/service/BUILD.gn

 # Copyright 2014 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.
 
 import("//build/config/ui.gni")
 import("//third_party/protobuf/proto_library.gni")
 
 source_set("service") {
   sources = [
     "async_pixel_transfer_delegate.cc",
@@ skipping 51 matching lines @@
     "gl_utils.h",
     "gpu_scheduler.cc",
     "gpu_scheduler.h",
     "gpu_scheduler_mock.h",
     "gpu_state_tracer.cc",
     "gpu_state_tracer.h",
     "gpu_switches.cc",
     "gpu_switches.h",
     "gpu_tracer.cc",
     "gpu_tracer.h",
+    "gpu_timing.cc",
+    "gpu_timing.h",
     "id_manager.h",
     "id_manager.cc",
     "image_factory.cc",
     "image_factory.h",
     "image_manager.cc",
     "image_manager.h",
     "in_process_command_buffer.cc",
     "in_process_command_buffer.h",
     "logger.cc",
     "logger.h",
@@ skipping 77 matching lines @@
     configs -= [ "//build/config/compiler:optimize" ]
     configs += [ "//build/config/compiler:optimize_max" ]
   }
 }
 
 proto_library("disk_cache_proto") {
   sources = [
     "disk_cache_proto.proto",
   ]
 }