Extract DeclarativeUserScriptManager from ExtensionSystem.

extensions/browser/declarative_user_script_manager.cc

 // 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.
 
 #include "extensions/browser/declarative_user_script_manager.h"
 
 #include "content/public/browser/browser_context.h"
+#include "extensions/browser/declarative_user_script_manager_factory.h"
 #include "extensions/browser/declarative_user_script_master.h"
 #include "extensions/browser/extension_registry.h"
 
 namespace extensions {
 
 DeclarativeUserScriptManager::DeclarativeUserScriptManager(
     content::BrowserContext* browser_context)
     : browser_context_(browser_context), extension_registry_observer_(this) {
   extension_registry_observer_.Add(ExtensionRegistry::Get(browser_context));
 }
 
 DeclarativeUserScriptManager::~DeclarativeUserScriptManager() {
 }
 
+// static
+DeclarativeUserScriptManager* DeclarativeUserScriptManager::Get(
+    content::BrowserContext* browser_context) {
+  return DeclarativeUserScriptManagerFactory::GetForBrowserContext(
+      browser_context);
+}
+
 DeclarativeUserScriptMaster*
 DeclarativeUserScriptManager::GetDeclarativeUserScriptMasterByID(
     const HostID& host_id) {
   UserScriptMasterMap::iterator it =
       declarative_user_script_masters_.find(host_id);
 
   if (it != declarative_user_script_masters_.end())
     return it->second.get();
 
   return CreateDeclarativeUserScriptMaster(host_id);
@@ skipping 13 matching lines @@
     const Extension* extension,
     UnloadedExtensionInfo::Reason reason) {
   for (const auto& val : declarative_user_script_masters_) {
     DeclarativeUserScriptMaster* master = val.second.get();
     if (master->host_id().id() == extension->id())
       master->ClearScripts();
   }
 }
 
 }  // namespace extensions