Check for guest renderer before casting to RenderWidgetHostViewAura in

content/browser/web_contents/web_contents_view_aura.cc

 // Copyright (c) 2012 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/web_contents/web_contents_view_aura.h"
 
 #include "base/auto_reset.h"
 #include "base/metrics/histogram.h"
 #include "base/utf_string_conversions.h"
 #include "content/browser/renderer_host/dip_util.h"
@@ skipping 79 matching lines @@
 }
 
 bool ShouldNavigateBack(const NavigationController& controller,
                         OverscrollMode mode) {
   return mode == (base::i18n::IsRTL() ? OVERSCROLL_WEST : OVERSCROLL_EAST) &&
          controller.CanGoBack();
 }
 
 RenderWidgetHostViewAura* ToRenderWidgetHostViewAura(
     RenderWidgetHostView* view) {
-  if (RenderViewHostFactory::has_factory())
+  if (!view || RenderViewHostFactory::has_factory())
     return NULL;  // Can't cast to RenderWidgetHostViewAura in unit tests.
+  RenderProcessHostImpl* process = static_cast<RenderProcessHostImpl*>(
+      view->GetRenderWidgetHost()->GetProcess());
+  if (process->IsGuest())
+    return NULL;
   return static_cast<RenderWidgetHostViewAura*>(view);
 }
 
 // The window delegate for the overscroll window. This redirects trackpad events
 // to the web-contents window. The delegate destroys itself when the window is
 // destroyed.
 class OverscrollWindowDelegate : public aura::WindowDelegate {
  public:
   OverscrollWindowDelegate(WebContentsImpl* web_contents,
                            OverscrollMode overscroll_mode)
@@ skipping 1581 matching lines @@
       event.location(),
       gfx::Screen::GetScreenFor(GetNativeView())->GetCursorScreenPoint(),
       ConvertAuraEventFlagsToWebInputEventModifiers(event.flags()));
   if (drag_dest_delegate_)
     drag_dest_delegate_->OnDrop();
   current_drop_data_.reset();
   return current_drag_op_;
 }
 
 }  // namespace content