[DevTools] Remove HandlerRegistry.

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 48 matching lines @@
   "front_end/components/networkConditionsSettingsTab.css",
   "front_end/components/objectPropertiesSection.css",
   "front_end/components/objectValue.css",
   "front_end/components/spectrum.css",
   "front_end/components/CustomPreviewSection.js",
   "front_end/components/DataSaverInfobar.js",
   "front_end/components/DockController.js",
   "front_end/components/DOMBreakpointsSidebarPane.js",
   "front_end/components/DOMPresentationUtils.js",
   "front_end/components/ExecutionContextSelector.js",
-  "front_end/components/HandlerRegistry.js",
   "front_end/components/JavaScriptAutocomplete.js",
   "front_end/components/BreakpointsSidebarPaneBase.js",
   "front_end/components/Linkifier.js",
   "front_end/components/NetworkConditionsSelector.js",
   "front_end/components/ObjectPopoverHelper.js",
   "front_end/components/ObjectPropertiesSection.js",
   "front_end/components/RemoteObjectPreviewFormatter.js",
   "front_end/components/RequestAppBannerActionDelegate.js",
   "front_end/components/ShortcutsScreen.js",
   "front_end/components/Spectrum.js",
@@ skipping 1069 matching lines @@
     deps = [
       ":frontend_protocol_sources",
       ":supported_css_properties",
     ]
     sources = generated_scripts
     outputs = [
       "$resources_out_debug_dir/{{source_file_part}}",
     ]
   }
 }