Allow MimeHandlerViewGuest be embedded inside OOPIFs

content/public/browser/browser_plugin_guest_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_PUBLIC_BROWSER_BROWSER_PLUGIN_GUEST_DELEGATE_H_
 #define CONTENT_PUBLIC_BROWSER_BROWSER_PLUGIN_GUEST_DELEGATE_H_
 
 #include "base/callback_forward.h"
 #include "base/process/kill.h"
 #include "content/common/content_export.h"
@@ skipping 79 matching lines @@
   // Sets the position of the context menu for the guest contents. The value
   // reported from the guest renderer should be ignored. The reported value
   // fromt he guest renderer is incorrect in situations where BrowserPlugin is
   // subject to CSS transforms.
   virtual void SetContextMenuPosition(const gfx::Point& position) {}
 
   // TODO(ekaramad): A short workaround to force some types of guests to use
   // a BrowserPlugin even when we are using cross process frames for guests. It
   // should be removed after resolving https://crbug.com/642826).
   virtual bool CanUseCrossProcessFrames();
+
+  // Returns the RenderFrameHost corresponding to the RenderFrame embedding the
+  // BrowserPlugin. This is the main frame for the owner of the guests, unless,
+  // the guest is embedded inside a cross origin frame.
+  virtual RenderFrameHost* GetEmbedderFrame();
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_BROWSER_PLUGIN_GUEST_DELEGATE_H_