Remove WebContents::Was{Hidden,Shown}() from the content public interface

chrome/browser/ui/webui/print_preview/print_preview_distiller.cc

 // Copyright 2015 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 "chrome/browser/ui/webui/print_preview/print_preview_distiller.h"
 
 #include <stdint.h>
 #include <string>
 #include <utility>
 
@@ skipping 150 matching lines @@
     if (details.resource_type != content::RESOURCE_TYPE_MAIN_FRAME)
       return;
     // Redirects are unsupported for distilled content renderers.
     on_failed_callback_.Run();
   }
 
   void RenderProcessGone(base::TerminationStatus status) override {
     on_failed_callback_.Run();
   }
 
+  // Note: This is copy-pasted from PrerenderContents::Observe().
   void Observe(int type,
                const content::NotificationSource& source,
                const content::NotificationDetails& details) override {
     switch (type) {
       // TODO(davidben): Try to remove this in favor of relying on
       // FINAL_STATUS_PROFILE_DESTROYED.
       case chrome::NOTIFICATION_APP_TERMINATING:
         on_failed_callback_.Run();
         return;
 
       case content::NOTIFICATION_WEB_CONTENTS_RENDER_VIEW_HOST_CREATED: {
         if (web_contents()) {
           DCHECK_EQ(content::Source<WebContents>(source).ptr(), web_contents());
 
           // Make sure the size of the RenderViewHost has been passed to the new
           // RenderView.  Otherwise, the size may not be sent until the
           // RenderViewReady event makes it from the render process to the UI
           // thread of the browser process.  When the RenderView receives its
           // size, is also sets itself to be visible, which would then break the
           // visibility API.
           content::Details<RenderViewHost> new_render_view_host(details);
           new_render_view_host->GetWidget()->WasResized();
-          web_contents()->WasHidden();
+          web_contents()->MarkBackgrounded();
         }
         break;
       }
 
       default:
         NOTREACHED() << "Unexpected notification sent.";
         break;
     }
   }
 
@@ skipping 70 matching lines @@
     WebContents* source_web_contents) {
   // TODO(ajwong): Remove the temporary map once prerendering is aware of
   // multiple session storage namespaces per tab.
   content::SessionStorageNamespaceMap session_storage_namespace_map;
   Profile* profile =
       Profile::FromBrowserContext(source_web_contents->GetBrowserContext());
   session_storage_namespace_map[std::string()] = session_storage_namespace;
   return WebContents::CreateWithSessionStorage(
       WebContents::CreateParams(profile), session_storage_namespace_map);
 }