DevTools: migrate StylesSidebarPane to shadow

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")
 
 all_devtools_files = [
   "front_end/accessibility/AccessibilityModel.js",
@@ skipping 179 matching lines @@
   "front_end/elements/EventListenersWidget.js",
   "front_end/elements/InspectElementModeController.js",
   "front_end/elements/metricsSidebarPane.css",
   "front_end/elements/MetricsSidebarPane.js",
   "front_end/elements/module.json",
   "front_end/elements/platformFontsWidget.css",
   "front_end/elements/PlatformFontsWidget.js",
   "front_end/elements/PropertiesWidget.js",
   "front_end/elements/StylePropertyHighlighter.js",
   "front_end/elements/stylesSectionTree.css",
+  "front_end/elements/stylesSidebarPane.css",
   "front_end/elements/StylesSidebarPane.js",
   "front_end/emulated_devices/module.json",
   "front_end/emulation/AdvancedApp.js",
   "front_end/emulation/DeviceModeModel.js",
   "front_end/emulation/deviceModeToolbar.css",
   "front_end/emulation/DeviceModeToolbar.js",
   "front_end/emulation/deviceModeView.css",
   "front_end/emulation/DeviceModeView.js",
   "front_end/emulation/DeviceModeWrapper.js",
   "front_end/emulation/devicesSettingsTab.css",
@@ skipping 949 matching lines @@
     ".eslintrc.js",
     "devtools-node-modules/",
     "front_end/",
     "scripts/buildbot/run_eslint.py",
     "scripts/local_node/",
     "//testing/scripts/common.py",
     "//testing/scripts/run_devtools_check.py",
     "//testing/xvfb.py",
   ]
 }