From 902e25cb1d7d3daf9b2258d31266551e9ae70736 Mon Sep 17 00:00:00 2001
From: Timo Tijhof <krinklemail@gmail.com>
Date: Tue, 21 Feb 2017 14:43:46 -0800
Subject: [PATCH] mediawiki.requestIdleCallback: Re-enable use of native
 requestIdleCallback

Follows-up 63416b009fb82e, which disabled this due to a Chrome
bug that caused it to sometimes not schedule callbacks for a period
upto 30 seconds.

<https://bugs.chromium.org/p/chromium/issues/detail?id=647870>

This issue since been closed and I can no longer reproduce it
using a demo at <http://codepen.io/Krinkle/full/XNGEvv>.

Change-Id: I4e8dc21e6106e1d2474daed0f25712fd5a7e46f8
---
 .../src/mediawiki/mediawiki.requestIdleCallback.js  | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/resources/src/mediawiki/mediawiki.requestIdleCallback.js b/resources/src/mediawiki/mediawiki.requestIdleCallback.js
index d414232010..6a6aa155ce 100644
--- a/resources/src/mediawiki/mediawiki.requestIdleCallback.js
+++ b/resources/src/mediawiki/mediawiki.requestIdleCallback.js
@@ -43,12 +43,11 @@
 	 *  immediate execution after this amount of time (in milliseconds) if it didn't run
 	 *  by that time.
 	 */
-	mw.requestIdleCallback = mw.requestIdleCallbackInternal;
-	/*
-	// XXX: Polyfill disabled due to https://bugs.chromium.org/p/chromium/issues/detail?id=647870
-	mw.requestIdleCallback = window.requestIdleCallback
+	mw.requestIdleCallback = window.requestIdleCallback ?
 		// Bind because it throws TypeError if context is not window
-		? window.requestIdleCallback.bind( window )
-		: mw.requestIdleCallbackInternal;
-	*/
+		window.requestIdleCallback.bind( window ) :
+		mw.requestIdleCallbackInternal;
+	// Note: Polyfill was previously disabled due to
+	// https://bugs.chromium.org/p/chromium/issues/detail?id=647870
+	// See also <http://codepen.io/Krinkle/full/XNGEvv>
 }( mediaWiki ) );
-- 
2.20.1