Allow a main interstitial frame to act as an ExtensionMessagePort opener

content/browser/frame_host/render_frame_host_delegate.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.
 
 #ifndef CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_DELEGATE_H_
 #define CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_DELEGATE_H_
 
 #include <stdint.h>
 
 #include <vector>
@@ skipping 13 matching lines @@
 #endif
 
 class GURL;
 
 namespace IPC {
 class Message;
 }
 
 namespace content {
 class GeolocationServiceContext;
+class InterstitialPage;
 class PageState;
 class RenderFrameHost;
 class WakeLockServiceContext;
 class WebContents;
 struct AXEventNotificationDetails;
 struct ContextMenuParams;
 struct TransitionLayerData;
 
 // An interface implemented by an object interested in knowing about the state
 // of the RenderFrameHost.
@@ skipping 65 matching lines @@
 
   // The page's encoding was changed and should be updated. Only called for the
   // top-level frame.
   virtual void UpdateEncoding(RenderFrameHost* render_frame_host,
                               const std::string& encoding) {}
 
   // Return this object cast to a WebContents, if it is one. If the object is
   // not a WebContents, returns NULL.
   virtual WebContents* GetAsWebContents();
 
+  // Returns this object cast to an InterstitialPage if it is one. Returns
+  // nullptr otherwise.
+  virtual InterstitialPage* GetAsInterstitialPage();

[Charlie Reis, 2016/01/25 21:47:38]

Yeah, I suppose we can use this pattern again.  I'll be glad to see it go away
when interstitials are refactored to be committed pages, but it makes sense for
the time being.

[robwu, 2016/01/25 22:54:41]

Acknowledged.

+
   // The render frame has requested access to media devices listed in
   // |request|, and the client should grant or deny that permission by
   // calling |callback|.
   virtual void RequestMediaAccessPermission(
       const MediaStreamRequest& request,
       const MediaResponseCallback& callback);
 
   // Checks if we have permission to access the microphone or camera. Note that
   // this does not query the user. |type| must be MEDIA_DEVICE_AUDIO_CAPTURE
   // or MEDIA_DEVICE_VIDEO_CAPTURE.
@@ skipping 55 matching lines @@
   virtual gfx::NativeViewAccessible GetParentNativeViewAccessible();
 #endif
 
  protected:
   virtual ~RenderFrameHostDelegate() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_DELEGATE_H_