Remove unneeded parameter hockey in event shortcuts.

src/event.js

@@ -967,11 +967,6 @@ jQuery.each( ("blur focus focusin focusout load resize scroll unload click dblcl
 
 	// Handle event binding
 	jQuery.fn[ name ] = function( data, fn ) {
-		if ( fn == null ) {
-			fn = data;
-			data = null;
-		}
-
 		return arguments.length > 0 ?
 			this.on( name, null, data, fn ) :
 			this.trigger( name );