From 2c8df0f63732f1164682d8ec6d9e1a733909de82 Mon Sep 17 00:00:00 2001
From: Jason Cheatham <j.cheatham@gmail.com>
Date: Fri, 24 Feb 2017 06:07:43 -0700
Subject: [PATCH] fixes #17716, sporadic gesture/tap error

---
 gesture/tap.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/gesture/tap.js b/gesture/tap.js
index 10ad030d1b..ca3f78acfa 100644
--- a/gesture/tap.js
+++ b/gesture/tap.js
@@ -129,6 +129,9 @@ var clz = declare(/*===== "dojox.gesture.tap", =====*/Base, {
 	_isTap: function(/*Object*/data, /*Event*/e){
 		// summary:
 		//		Check whether it's an valid tap
+		if (!data.context) {
+			return false;
+		}
 		var dx = Math.abs(data.context.x - e.screenX);
 		var dy = Math.abs(data.context.y - e.screenY);
 		return dx <= this.tapRadius && dy <= this.tapRadius;
@@ -142,4 +145,4 @@ dojox.gesture.tap.Tap = clz;
 
 return dojox.gesture.tap;
 
-});
\ No newline at end of file
+});