Fire visibilityChange event on out-of-process iframes.

components/plugins/renderer/webview_plugin.cc

 // 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.
 
 #include "components/plugins/renderer/webview_plugin.h"
 
 #include <stddef.h>
 
 #include "base/auto_reset.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 36 matching lines @@
 using blink::WebVector;
 using blink::WebView;
 using content::WebPreferences;
 
 WebViewPlugin::WebViewPlugin(content::RenderView* render_view,
                              WebViewPlugin::Delegate* delegate,
                              const WebPreferences& preferences)
     : content::RenderViewObserver(render_view),
       delegate_(delegate),
       container_(nullptr),
-      web_view_(WebView::create(this)),
+      web_view_(WebView::create(this, true)),
       finished_loading_(false),
       focused_(false),
       is_painting_(false),
       is_resizing_(false) {
   // ApplyWebPreferences before making a WebLocalFrame so that the frame sees a
   // consistent view of our preferences.
   content::RenderView::ApplyWebPreferences(preferences, web_view_);
   WebLocalFrame* web_local_frame =
       WebLocalFrame::create(blink::WebTreeScopeType::Document, this);
   web_frame_ = web_local_frame;
@@ skipping 272 matching lines @@
   // By default RenderViewObservers are destroyed along with the RenderView.
   // WebViewPlugin has a custom destruction mechanism, so we disable this.
 }
 
 void WebViewPlugin::OnZoomLevelChanged() {
   if (container_) {
     web_view_->setZoomLevel(
       blink::WebView::zoomFactorToZoomLevel(container_->pageZoomFactor()));
   }
 }