Mouse: Always call event.preventDefault() in _mouseDown if we've met …

…the starting conditions. Fixes #6174 - Mouse: 1.4.3rc2 breaks interactions on anchors.

ui/jquery.ui.mouse.js

@@ -86,11 +86,7 @@ $.widget("ui.mouse", {
 			.bind('mousemove.'+this.widgetName, this._mouseMoveDelegate)
 			.bind('mouseup.'+this.widgetName, this._mouseUpDelegate);
 
-		// preventDefault() is used to prevent the selection of text here -
-		// however, in Safari, this causes select boxes not to be selectable
-		// anymore, so this fix is needed
-		($.browser.safari || event.preventDefault());
-
+		event.preventDefault();
 		event.originalEvent.mouseHandled = true;
 		return true;
 	},