Remove unusued WebFrameClient::willRequestResource and WebCachedURLRequest

public/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("//tools/grit/grit_rule.gni")
 
 if (is_android) {
   import("//build/config/android/rules.gni")
 }
 
@@ skipping 517 matching lines @@
     "web/WebDOMFileSystem.h",
     "web/WebPopupType.h",
     "web/WebNodeList.h",
     "web/WebPluginContainer.h",
     "web/WebGeolocationPermissionRequestManager.h",
     "web/WebRemoteFrame.h",
     "web/WebPlugin.h",
     "web/WebKit.h",
     "web/WebPageSerializer.h",
     "web/WebPluginAction.h",
-    "web/WebCachedURLRequest.h",
     "web/WebSecurityOrigin.h",
     "web/WebFrameWidget.h",
     "web/WebColorChooser.h",
     "web/WebContextMenuData.h",
     "web/WebURLLoaderOptions.h",
     "web/WebNetworkStateNotifier.h",
     "web/WebScriptSource.h",
     "web/WebBindings.h",
     "web/WebSerializedScriptValueVersion.h",
     "web/WebGlyphCache.h",
@@ skipping 99 matching lines @@
 grit("image_resources") {
   output_dir = "$root_gen_dir/blink/public/resources"
   use_qualified_include = true
   source = "blink_image_resources.grd"
   outputs = [
     "grit/blink_image_resources.h",
     "blink_image_resources_100_percent.pak",
     "blink_image_resources_200_percent.pak",
   ]
 }