[iOS] Upstream web_controller_provider_impl.{h,mm}.

ios/public/provider/web/web_controller_provider.mm

 // Copyright 2015 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.
 
 #include "ios/public/provider/web/web_controller_provider.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 namespace ios {
 
-static WebControllerProviderFactory* g_web_controller_provider_factory;
-
-void SetWebControllerProviderFactory(
-    WebControllerProviderFactory* provider_factory) {
-  g_web_controller_provider_factory = provider_factory;
-}
-
-WebControllerProviderFactory* GetWebControllerProviderFactory() {
-  return g_web_controller_provider_factory;
-}
-
 WebControllerProvider::WebControllerProvider(web::BrowserState* browser_state) {
 }
 
-WebControllerProvider::~WebControllerProvider() {
-}
+WebControllerProvider::~WebControllerProvider() {}
 
 bool WebControllerProvider::SuppressesDialogs() const {
   return false;
 }
 
 web::WebState* WebControllerProvider::GetWebState() const {
   return nullptr;
 }
 
 void WebControllerProvider::InjectScript(
     const std::string& script,
     web::JavaScriptResultBlock completion) {
   if (completion)
     completion(nil, nil);
 }
 
-WebControllerProviderFactory::WebControllerProviderFactory() {
-}
-
-WebControllerProviderFactory::~WebControllerProviderFactory() {
-}
-
-std::unique_ptr<WebControllerProvider>
-WebControllerProviderFactory::CreateWebControllerProvider(
-    web::BrowserState* browser_state) {
-  return std::unique_ptr<WebControllerProvider>(
-      new WebControllerProvider(browser_state));
-}
-
 }  // namespace ios