[Devtools] Move canvas timeline out of experiments and remove old code

third_party/WebKit/Source/devtools/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("//third_party/WebKit/public/public_features.gni")
 import("//third_party/WebKit/Source/core/core.gni")
 
 devtools_embedder_scripts = [
   "front_end/devtools_compatibility.js",
@@ skipping 803 matching lines @@
   "front_end/Images/chromeRight.png",
   "front_end/Images/chromeSelect.png",
   "front_end/Images/chromeSelect_2x.png",
   "front_end/Images/deleteIcon.png",
   "front_end/Images/domain.png",
   "front_end/Images/errorWave.png",
   "front_end/Images/errorWave_2x.png",
   "front_end/Images/fileSystem.png",
   "front_end/Images/forward.png",
   "front_end/Images/frame.png",
-  "front_end/Images/graphLabelCalloutLeft.png",
-  "front_end/Images/graphLabelCalloutRight.png",
   "front_end/Images/ic_info_black_18dp.svg",
   "front_end/Images/ic_warning_black_18dp.svg",
   "front_end/Images/navigationControls.png",
   "front_end/Images/navigationControls_2x.png",
   "front_end/Images/paneAddButtons.png",
   "front_end/Images/paneFilterButtons.png",
   "front_end/Images/paneRefreshButtons.png",
   "front_end/Images/popoverArrows.png",
   "front_end/Images/profileGroupIcon.png",
   "front_end/Images/profileIcon.png",
@@ skipping 314 matching lines @@
     deps = [
       ":frontend_protocol_sources",
       ":supported_css_properties",
     ]
     sources = generated_scripts
     outputs = [
       "$resources_out_debug_dir/{{source_file_part}}",
     ]
   }
 }