Revert of Add support for entering/exiting HTML fullscreen from OOPIFs.

content/browser/web_contents/web_contents_impl.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_impl.h"
 
 #include <stddef.h>
 
 #include <cmath>
 #include <utility>
@@ skipping 1848 matching lines @@
     }
   }
 
   FOR_EACH_OBSERVER(WebContentsObserver, observers_,
                     DidToggleFullscreenModeForTab(
                         IsFullscreenForCurrentTab(
                             GetRenderViewHost()->GetWidget()),
                         will_cause_resize));
 }
 
-// TODO(alexmos): Remove the unused |render_widget_host| parameter.
 bool WebContentsImpl::IsFullscreenForCurrentTab(
     RenderWidgetHostImpl* render_widget_host) const {
+  if (!RenderViewHostImpl::From(render_widget_host))
+    return false;
+
   return delegate_ ? delegate_->IsFullscreenForTabOrPending(this) : false;
 }
 
 blink::WebDisplayMode WebContentsImpl::GetDisplayMode(
     RenderWidgetHostImpl* render_widget_host) const {
   if (!RenderViewHostImpl::From(render_widget_host))
     return blink::WebDisplayModeBrowser;
 
   return delegate_ ? delegate_->GetDisplayMode(this)
                    : blink::WebDisplayModeBrowser;
@@ skipping 3153 matching lines @@
   for (RenderViewHost* render_view_host : render_view_host_set)
     render_view_host->OnWebkitPreferencesChanged();
 }
 
 void WebContentsImpl::SetJavaScriptDialogManagerForTesting(
     JavaScriptDialogManager* dialog_manager) {
   dialog_manager_ = dialog_manager;
 }
 
 }  // namespace content