arc: enable Android tracing from chrome://tracing in dev mode

chrome/browser/chromeos/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/features.gni")
 import("//build/config/ui.gni")
 import("//extensions/features/features.gni")
 import("//media/media_options.gni")
 import("//printing/features/features.gni")
 import("//third_party/protobuf/proto_library.gni")
@@ skipping 295 matching lines @@
     "arc/policy/arc_policy_bridge.cc",
     "arc/policy/arc_policy_bridge.h",
     "arc/policy/arc_policy_util.cc",
     "arc/policy/arc_policy_util.h",
     "arc/print/arc_print_service.cc",
     "arc/print/arc_print_service.h",
     "arc/process/arc_process.cc",
     "arc/process/arc_process.h",
     "arc/process/arc_process_service.cc",
     "arc/process/arc_process_service.h",
+    "arc/trace/arc_trace_bridge.cc",

[Daniel Erat, 2017/03/08 15:41:13]

rename these to arc/tracing/arc_tracing_bridge?

a "trace" is the thing that gets generated, but "tracing" is what these classes
do. "tracing" seems more consistent with existing naming (see
chrome/browser/tracing/, components/tracing/, services/tracing/, etc.).

[Earl Ou, 2017/03/09 06:08:41]

Done. I also change mojom interface to tracing.mojo, TracingInstance etc. On
Android side, it will still be arctraceservice instead of arctracingservice as
we have 16 character limit for service name.

+    "arc/trace/arc_trace_bridge.h",
     "arc/tts/arc_tts_service.cc",
     "arc/tts/arc_tts_service.h",
     "arc/video/gpu_arc_video_service_host.cc",
     "arc/video/gpu_arc_video_service_host.h",
     "arc/wallpaper/arc_wallpaper_service.cc",
     "arc/wallpaper/arc_wallpaper_service.h",
     "attestation/attestation_ca_client.cc",
     "attestation/attestation_ca_client.h",
     "attestation/attestation_policy_observer.cc",
     "attestation/attestation_policy_observer.h",
@@ skipping 1468 matching lines @@
     "policy/proto/chrome_device_policy.proto",
     "policy/proto/install_attributes.proto",
   ]
 }
 
 proto_library("attestation_proto") {
   sources = [
     "attestation/attestation_key_payload.proto",
   ]
 }