Move allocate instance id to chrome/.

content/public/browser/browser_plugin_guest_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 "content/public/browser/browser_plugin_guest_manager.h"
 
 #include "base/values.h"
 
 namespace content {
 
 content::WebContents* BrowserPluginGuestManager::CreateGuest(
     SiteInstance* embedder_site_instance,
     int instance_id,
-    const std::string& storage_partition_id,
-    bool persist_storage,
     scoped_ptr<base::DictionaryValue> extra_params) {
   return NULL;
 }
 
 int BrowserPluginGuestManager::GetNextInstanceID() {
   return 0;
 }
 
 bool BrowserPluginGuestManager::ForEachGuest(
     WebContents* embedder_web_contents,
     const GuestCallback& callback) {
   return false;
 }
 
 }  // content