make StackingClient dispatch to either ash or desktop

chrome/browser/prerender/prerender_manager.cc

 // Copyright (c) 2012 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 "chrome/browser/prerender/prerender_manager.h"
 
 #include <algorithm>
 #include <functional>
 #include <string>
 #include <vector>
@@ skipping 218 matching lines @@
 PrerenderHandle* PrerenderManager::AddPrerenderFromLinkRelPrerender(
     int process_id,
     int route_id,
     const GURL& url,
     const content::Referrer& referrer,
     const gfx::Size& size) {
 #if defined(OS_ANDROID)
   // TODO(jcivelli): http://crbug.com/113322 We should have an option to disable
   //                link-prerender and enable omnibox-prerender only.
   return NULL;
+#elif defined(OS_WIN) && defined(USE_AURA)
+  // TODO(scottmg): http://crbug.com/128578 WebContentsViewAura can't get a
+  // valid parent window here.
+  return NULL;
 #else
   DCHECK(!size.IsEmpty());
   Origin origin = ORIGIN_LINK_REL_PRERENDER_CROSSDOMAIN;
   SessionStorageNamespace* session_storage_namespace = NULL;
   // Unit tests pass in a process_id == -1.
   if (process_id != -1) {
     RenderViewHost* source_render_view_host =
         RenderViewHost::FromID(process_id, route_id);
     if (!source_render_view_host)
       return NULL;
@@ skipping 1127 matching lines @@
   if (!render_process_host || !render_process_host->GetBrowserContext())
     return NULL;
   Profile* profile = Profile::FromBrowserContext(
       render_process_host->GetBrowserContext());
   if (!profile)
     return NULL;
   return PrerenderManagerFactory::GetInstance()->GetForProfile(profile);
 }
 
 }  // namespace prerender