Allow webview API in an unblessed extension process

content/browser/browser_plugin/browser_plugin_guest_manager.h

 // 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.
 
 // A BrowserPluginGuestManager serves as a message router to BrowserPluginGuests
 // for all guests within a given profile.
 // Messages are routed to a particular guest instance based on an instance_id.
 
 #ifndef CONTENT_BROWSER_BROWSER_PLUGIN_BROWSER_PLUGIN_GUEST_MANAGER_H_
 #define CONTENT_BROWSER_BROWSER_PLUGIN_BROWSER_PLUGIN_GUEST_MANAGER_H_
@@ skipping 20 matching lines @@
 
 class BrowserPluginGuest;
 class BrowserPluginHostFactory;
 class RenderProcessHostImpl;
 class RenderWidgetHostImpl;
 class SiteInstance;
 class WebContents;
 class WebContentsImpl;
 struct NativeWebKeyboardEvent;
 
+// WARNING: BrowserPlugin could be loaded in an unblessed context, thus any new

[Charlie Reis, 2013/09/25 17:25:18]

This part isn't quite right-- BrowserPlugins can't be loaded in unblessed
contexts.  It's the webview API that's available (though I agree we shouldn't
talk about webviews in content/).

Maybe just leave out the first part:
WARNING: All APIs should be guarded with a process ID check like
CanEmbedderAccessInstanceIDMaybeKill, to prevent abuse by normal renderer
processes.

[guohui, 2013/09/25 22:43:51]

Done.

+// APIs must be guarded with process ID check to prevent abuse by normal
+// renderer processes.
 class CONTENT_EXPORT BrowserPluginGuestManager :
     public base::SupportsUserData::Data {
  public:
   virtual ~BrowserPluginGuestManager();
 
   static BrowserPluginGuestManager* Create();
 
   // Overrides factory for testing. Default (NULL) value indicates regular
   // (non-test) environment.
   static void set_factory_for_testing(BrowserPluginHostFactory* factory) {
@@ skipping 77 matching lines @@
   GuestInstanceMap guest_web_contents_by_instance_id_;
   int next_instance_id_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserPluginGuestManager);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_BROWSER_PLUGIN_BROWSER_PLUGIN_GUEST_MANAGER_H_