Menu: _focus function forgets null check with doing a pattern match on event.type

Sorry to report as a bug instead of just fixing myself, but i have to run and wouldn't want to modify without running all the unit tests.

ISSUE: ui.menu widget's focus function forgets null check with doing a pattern match on event.type. The UI Menu API documentation even gives the menu("focus",...) example passing null as the event argument. And focus gets triggered from a variety of other cases, which means that due to this other events aren't able to be called as suggested in the API docs.

Browser: Chrome

Noticed in ui 1.10.2 (line 11774), found to still be present in 1.10.3 (line 11790)

problematic code:

if ( nested.length && ( /^mouse/.test( event.type ) ) ) {

this._startOpening(nested);

}

correction suggestion:

if ( nested.length && event && ( /^mouse/.test( event.type ) ) ) {

this._startOpening(nested);

}

I have already found a work around, which is to always pass the supposedly optional event argument. But it's not ideal. here is my working code, without eventObj argument it fails, i am just prototyping for now, but i will be using this with non-mouse events to position a menu where the mouse is.

var menuHolder = $(menuHTML).appendTo($("body")).menu(menuOptions);

menuHolder.menu("next", eventObj);

menuHolder.menu("expand", eventObj);

//bind the events for disposing of the context menu

$("body").find("*").not($("button#testContextMenu, .ContextMenuHolder, .ContextMenuHolder *")).mousedown(closeContextMenu);