Change ol.BrowserFeature.HAS_POINTER feature detection

Because navigator.pointerEnabled will not be part of the final spec.
See https://www.w3.org/Bugs/Public/show_bug.cgi?id=22890

externs/closure-compiler.js

@@ -52,12 +52,3 @@ Document.prototype.msFullscreenEnabled;
 
 /** @type {Element} */
 Document.prototype.msFullscreenElement;
-
-
-// @see https://code.google.com/p/closure-compiler/issues/detail?id=1276
-
-/**
- * @type {boolean}
- * @see http://www.w3.org/TR/pointerevents/#widl-Navigator-pointerEnabled
- */
-Navigator.prototype.pointerEnabled;

src/ol/browserfeature.js

@@ -164,16 +164,11 @@ ol.BrowserFeature.HAS_TOUCH = ol.ASSUME_TOUCH ||
 
 /**
  * True if browser supports pointer events.
- *
- * `navigation.pointerEnabled` is actually not part of the
- * spec: https://www.w3.org/Bugs/Public/show_bug.cgi?id=22890#c3
- *
  * @const
  * @type {boolean}
  * @todo stability experimental
  */
-ol.BrowserFeature.HAS_POINTER =
+ol.BrowserFeature.HAS_POINTER = 'PointerEvent' in goog.global;
-    !!(goog.global.navigator.pointerEnabled);
 
 
 /**