Allow MimeHandlerViewGuest be embedded inside OOPIFs

content/public/browser/guest_host.h

 // Copyright 2015 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_PUBLIC_BROWSER_GUEST_HOST_H_
 #define CONTENT_PUBLIC_BROWSER_GUEST_HOST_H_
 
 #include "ui/gfx/geometry/size.h"
 
 namespace content {
 
+class WebContents;
+
 // A GuestHost is the content API for a guest WebContents.
 // Guests are top-level frames that can be embedded within other pages.
 // The content module manages routing of input events and compositing, but all
 // other operations are managed outside of content. To limit exposure of
 // implementation details within content, content embedders must use this
 // interface for loading, sizing, and cleanup of guests.
 //
 // This class currently only serves as a base class for BrowserPluginGuest, and
 // its API can only be accessed by a BrowserPluginGuestDelegate.
 class GuestHost {
  public:
   // Loads a URL using the specified |load_params| and returns a routing ID for
   // a proxy for the guest.
   virtual int LoadURLWithParams(
       const NavigationController::LoadURLParams& load_params) = 0;
 
   // Called when the GuestHost's size changes due to auto resize.
   virtual void GuestResizeDueToAutoResize(const gfx::Size& new_size) = 0;
 
   // Sets the size of the guest WebContents.
   virtual void SizeContents(const gfx::Size& new_size) = 0;
 
   // Called when the GuestHost is about to be destroyed.
   virtual void WillDestroy() = 0;
+
+  // Registers the |process_id| and |routing_id| of the embedder frame for this
+  // guest and returns the WebContents associated with the frame.
+  virtual WebContents* RegisterEmbedderID(int process_id, int routing_id) = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_GUEST_HOST_H_