Rework some UserScriptLoader logic in preparation to removing UserScript copy.

extensions/browser/web_ui_user_script_loader.cc

 // 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 "extensions/browser/web_ui_user_script_loader.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/strings/string_util.h"
@@ skipping 30 matching lines @@
     content::BrowserContext* browser_context,
     const HostID& host_id)
     : UserScriptLoader(browser_context, host_id), complete_fetchers_(0) {
   SetReady(true);
 }
 
 WebUIUserScriptLoader::~WebUIUserScriptLoader() {
 }
 
 void WebUIUserScriptLoader::AddScripts(
-    const std::set<extensions::UserScript>& scripts,
+    const extensions::UserScriptList& scripts,
     int render_process_id,
     int render_view_id) {
   UserScriptRenderInfo info(render_process_id, render_view_id);
   for (const extensions::UserScript& script : scripts) {
     script_render_info_map_.insert(
         std::pair<int, UserScriptRenderInfo>(script.id(), info));
   }
 
   extensions::UserScriptLoader::AddScripts(scripts);
 }
@@ skipping 83 matching lines @@
   }
 }
 
 void WebUIUserScriptLoader::OnWebUIURLFetchComplete() {
   content::BrowserThread::PostTask(
       content::BrowserThread::FILE, FROM_HERE,
       base::Bind(&SerializeOnFileThread, base::Passed(&user_scripts_cache_),
                  scripts_loaded_callback_));
   scripts_loaded_callback_.Reset();
 }