Move ClosePage() from RenderViewHost to WebContents.

extensions/browser/process_manager.cc

 // Copyright 2013 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/process_manager.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram_macros.h"
@@ skipping 787 matching lines @@
     // Close remaining views.
     std::vector<content::RenderFrameHost*> frames_to_close;
     for (const auto& key_value : all_extension_frames_) {
       if (key_value.second.CanKeepalive() &&
           GetExtensionID(key_value.first) == extension_id) {
         DCHECK(!key_value.second.has_keepalive);
         frames_to_close.push_back(key_value.first);
       }
     }
     for (content::RenderFrameHost* frame : frames_to_close) {
-      frame->GetRenderViewHost()->ClosePage();
-      // RenderViewHost::ClosePage() may result in calling
+      content::WebContents::FromRenderFrameHost(frame)->ClosePage();

[Charlie Reis, 2015/04/29 17:31:18]

The interstitial CL reminded me that this might return null.  Should we add a
null check?

[nasko, 2015/04/29 21:15:33]

Should we ever be getting a background page RFH that has interstitial page? I
don't think it is possible, so I'm inclined to leave this as is and monitor if
we get any crashes.

[Charlie Reis, 2015/04/29 22:21:48]

I hadn't thought of a specific case it could happen; it just seemed unclear if
that was an invariant you intended to enforce.  Feel free to leave and monitor
for crashes.

+      // WebContents::ClosePage() may result in calling
       // UnregisterRenderViewHost() asynchronously and may cause race conditions
       // when the background page is reloaded.
       // To avoid this, unregister the view now.
       UnregisterRenderFrameHost(frame);
     }
 
     ExtensionHost* host = GetBackgroundHostForExtension(extension_id);
     if (host)
       CloseBackgroundHost(host);
   }
@@ skipping 95 matching lines @@
   if (extension && !IncognitoInfo::IsSplitMode(extension)) {
     BrowserContext* original_context =
         ExtensionsBrowserClient::Get()->GetOriginalContext(browser_context());
     return ProcessManager::Get(original_context)->GetSiteInstanceForURL(url);
   }
 
   return ProcessManager::GetSiteInstanceForURL(url);
 }
 
 }  // namespace extensions