Allow for pausing background tabs on desktop via about:flags.

chrome/renderer/chrome_content_renderer_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/renderer/chrome_content_renderer_client.h"
 
 #include <memory>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 1058 matching lines @@
 #else
   return true;
 #endif
 }
 
 bool ChromeContentRendererClient::
     AllowTimerSuspensionWhenProcessBackgrounded() {
 #if defined(OS_ANDROID)
   return true;
 #else
-  return false;
+  return base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kPauseBackgroundTabs);
 #endif
 }
 
 bool ChromeContentRendererClient::AllowPopup() {
 #if BUILDFLAG(ENABLE_EXTENSIONS)
   return ChromeExtensionsRendererClient::GetInstance()->AllowPopup();
 #else
   return false;
 #endif
 }
@@ skipping 427 matching lines @@
 
   RecordYouTubeRewriteUMA(result);
   return corrected_url.ReplaceComponents(r);
 }
 
 std::unique_ptr<base::TaskScheduler::InitParams>
 ChromeContentRendererClient::GetTaskSchedulerInitParams() {
   return task_scheduler_util::
       GetRendererTaskSchedulerInitParamsFromCommandLine();
 }