Expose the visibility state of a frame to the browser process.

chrome/browser/chrome_content_browser_client.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 "chrome/browser/chrome_content_browser_client.h"
 
 #include <set>
 #include <utility>
 #include <vector>
 
@@ skipping 2592 matching lines @@
 net::CookieStore*
 ChromeContentBrowserClient::OverrideCookieStoreForRenderProcess(
     int render_process_id) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   if (!prerender_tracker_)
     return NULL;
   return prerender_tracker_->GetPrerenderCookieStoreForRenderProcess(
                                  render_process_id).get();
 }
 
+void ChromeContentBrowserClient::OverridePageVisibilityState(
+      RenderFrameHost* render_frame_host,
+      blink::WebPageVisibilityState* visibility_state) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  WebContents* web_contents =
+      WebContents::FromRenderFrameHost(render_frame_host);
+  DCHECK(web_contents);
+
+  Profile* profile =
+      Profile::FromBrowserContext(web_contents->GetBrowserContext());
+  prerender::PrerenderManager* prerender_manager =
+      prerender::PrerenderManagerFactory::GetForProfile(profile);
+  if (prerender_manager &&
+      prerender_manager->IsWebContentsPrerendering(web_contents, nullptr)) {
+    *visibility_state = blink::WebPageVisibilityStatePrerender;
+  }
+}
+
 #if defined(ENABLE_WEBRTC)
 void ChromeContentBrowserClient::MaybeCopyDisableWebRtcEncryptionSwitch(
     base::CommandLine* to_command_line,
     const base::CommandLine& from_command_line,
     VersionInfo::Channel channel) {
 #if defined(OS_ANDROID)
   const VersionInfo::Channel kMaxDisableEncryptionChannel =
       VersionInfo::CHANNEL_BETA;
 #else
   const VersionInfo::Channel kMaxDisableEncryptionChannel =
       VersionInfo::CHANNEL_DEV;
 #endif
   if (channel <= kMaxDisableEncryptionChannel) {
     static const char* const kWebRtcDevSwitchNames[] = {
       switches::kDisableWebRtcEncryption,
     };
     to_command_line->CopySwitchesFrom(from_command_line,
                                       kWebRtcDevSwitchNames,
                                       arraysize(kWebRtcDevSwitchNames));
   }
 }
 #endif  // defined(ENABLE_WEBRTC)
 
 }  // namespace chrome