Force MimeHandlerView to always use BrowserPlugin

content/browser/frame_host/render_widget_host_view_guest.cc

 // Copyright 2014 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 "content/browser/frame_host/render_widget_host_view_guest.h"
 
 #include <utility>
 
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
@@ skipping 335 matching lines @@
 void RenderWidgetHostViewGuest::InitAsFullscreen(
     RenderWidgetHostView* reference_host_view) {
   // This should never get called.
   NOTREACHED();
 }
 
 gfx::NativeView RenderWidgetHostViewGuest::GetNativeView() const {
   if (!guest_)
     return gfx::NativeView();
 
-  RenderWidgetHostView* rwhv = guest_->GetOwnerRenderWidgetHostView();
+  if (guest_->IsMimeHandlerViewGuest())

[lazyboy, 2016/07/22 01:03:30]

I'm not sure I followed why this was needed.

Please add a comment why GetOwnerRWHV doesn't work.

[EhsanK, 2016/07/27 22:34:47]

If we have --use-cross-process-frames-for-guests and create an app
with a <webview> and set the webview.src to a pdf url, then:
1- webview will have a RenderWidgetHostViewChildFrame
2- webview is the embedder
3- PDF will have a RenderWidgetHostViewGuest.

Now GetOwneRenderWidgetHostView()->GetNativeView() crashes because of the
NOTREACHED() in RWHVCF.

After discussion with Lucas we decided to implement GetNativeView() for RWHVCF
instead. So this is reset to master.

+    return guest_->GetTopLevelRenderWidgetHostView()->GetNativeView();
+
+  RenderWidgetHostView* rwhv = GetOwnerRenderWidgetHostView();
   if (!rwhv)
     return gfx::NativeView();
+
   return rwhv->GetNativeView();
 }
 
 gfx::NativeViewAccessible RenderWidgetHostViewGuest::GetNativeViewAccessible() {
   if (!guest_)
     return gfx::NativeViewAccessible();
 
   RenderWidgetHostView* rwhv = guest_->GetOwnerRenderWidgetHostView();
   if (!rwhv)
     return gfx::NativeViewAccessible();
@@ skipping 269 matching lines @@
         gesture_event.data.scrollUpdate.inertialPhase ==
             blink::WebGestureEvent::MomentumPhase) {
       return;
     }
     host_->ForwardGestureEvent(gesture_event);
     return;
   }
 }
 
 }  // namespace content