Update prerender policy for custom tabs

chrome/browser/prerender/prerender_manager.h

 // 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.
 
 #ifndef CHROME_BROWSER_PRERENDER_PRERENDER_MANAGER_H_
 #define CHROME_BROWSER_PRERENDER_PRERENDER_MANAGER_H_
 
 #include <stdint.h>
 
 #include <list>
@@ skipping 116 matching lines @@
       const GURL& url,
       content::SessionStorageNamespace* session_storage_namespace,
       const gfx::Size& size);
 
   PrerenderHandle* AddPrerenderFromExternalRequest(
       const GURL& url,
       const content::Referrer& referrer,
       content::SessionStorageNamespace* session_storage_namespace,
       const gfx::Size& size);
 
+  PrerenderHandle* AddPrerenderOnCellularFromExternalRequest(

[mmenke, 2016/03/15 14:34:21]

Needs a comment explaining what it does

[Yusuf, 2016/03/20 06:48:29]

Done.

+      const GURL& url,
+      const content::Referrer& referrer,
+      content::SessionStorageNamespace* session_storage_namespace,
+      const gfx::Size& size);
+
   // Adds a prerender for Instant Search |url| if valid. The
   // |session_storage_namespace| matches the namespace of the active tab at the
   // time the prerender is generated. Returns a caller-owned PrerenderHandle* or
   // NULL.
   PrerenderHandle* AddPrerenderForInstant(
       const GURL& url,
       content::SessionStorageNamespace* session_storage_namespace,
       const gfx::Size& size);
 
   // Cancels all active prerenders.
@@ skipping 241 matching lines @@
 
   // Time window for which we record old navigations, in milliseconds.
   static const int kNavigationRecordWindowMs = 5000;
 
   void OnCancelPrerenderHandle(PrerenderData* prerender_data);
 
   // Returns whether prerendering is currently enabled or the reason why it is
   // disabled.
   chrome_browser_net::NetworkPredictionStatus GetPredictionStatus() const;
 
+  // Returns whether prerendering is currently enabled or the reason why it is
+  // disabled after taking into account the origin of the request.
+  chrome_browser_net::NetworkPredictionStatus GetPredictionStatusForOrigin(
+      Origin origin) const;
+
   // Adds a prerender for |url| from |referrer|. The |origin| specifies how the
   // prerender was added. If |size| is empty, then
   // PrerenderContents::StartPrerendering will instead use a default from
   // PrerenderConfig. Returns a PrerenderHandle*, owned by the caller, or NULL.
   PrerenderHandle* AddPrerender(
       Origin origin,
       const GURL& url,
       const content::Referrer& referrer,
       const gfx::Size& size,
       content::SessionStorageNamespace* session_storage_namespace);
@@ skipping 140 matching lines @@
   // Set of process hosts being prerendered.
   typedef std::set<content::RenderProcessHost*> PrerenderProcessSet;
   PrerenderProcessSet prerender_process_hosts_;
 
   DISALLOW_COPY_AND_ASSIGN(PrerenderManager);
 };
 
 }  // namespace prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_MANAGER_H_