Remove ol.control.Control.bindMouseOutFocusOutBlur function

It was a workaround added in #1761 to hide the button tooltip on
OSX / Chrome 32 and 33.

Because we're not using the tooltips anymore (see #2781) and this
version of chrome is deprecated this workaround can be removed.

src/ol/control/rotatecontrol.js

@@ -60,8 +60,6 @@ ol.control.Rotate = function(opt_options) {
   goog.events.listen(button, goog.events.EventType.CLICK,
       ol.control.Rotate.prototype.handleClick_, false, this);
 
-  ol.control.Control.bindMouseOutFocusOutBlur(button);
-
   var cssClasses = className + ' ' + ol.css.CLASS_UNSELECTABLE + ' ' +
       ol.css.CLASS_CONTROL;
   var element = goog.dom.createDom(goog.dom.TagName.DIV, cssClasses, button);