From aefd99ec7fcbef8d8013c0e451fb5b4552fbf3b5 Mon Sep 17 00:00:00 2001
From: Cheng Zhao <zcbenz@gmail.com>
Date: Wed, 3 Aug 2016 10:40:12 +0900
Subject: [PATCH] Only enable kEnableBeginFrameScheduling for offscreen

It has effects on performance and only gets turned on after Chrome 54.
---
 atom/browser/web_contents_preferences.cc | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/atom/browser/web_contents_preferences.cc b/atom/browser/web_contents_preferences.cc
index fb28a79dd37..49a42a3ee12 100644
--- a/atom/browser/web_contents_preferences.cc
+++ b/atom/browser/web_contents_preferences.cc
@@ -187,7 +187,11 @@ void WebContentsPreferences::AppendExtraCommandLineSwitches(
       command_line->AppendSwitch("hidden-page");
   }
 
-  command_line->AppendSwitch(cc::switches::kEnableBeginFrameScheduling);
+  // Use frame scheduling for offscreen renderers.
+  // TODO(zcbenz): Remove this after Chrome 54, on which it becomes default.
+  bool offscreen;
+  if (web_preferences.Get("offscreen", &offscreen) && offscreen)
+    command_line->AppendSwitch(cc::switches::kEnableBeginFrameScheduling);
 }
 
 // static