mediawiki.htmlform: Refactor and clean up
* Use .filter function instead of concatenating strings.
The end result is the same.
It's faster and more stable and semantically correct this way
because using the string syntax is subject to bugs when using
special characters (you'd have to escape it first, which is
non-trivial to do in CSS selectors, sometimes impossible).
So comparing the .name property against a string value directly
is much easier.
* Use .prop() instead of .attr() where appropiate.
attr() changes attribute nodes only in the DOM, properties
reflect the actual live rendered value. This works because of
a back-compat layer in jQuery, but has been deprecated.
* Use a simple array and create 1 jQuery object, instead of
creating various temporary objects only to have jQuery merge
them via .add(). .add() is relatively expensive in that it
keeps a reference in pushStack and does a lot of logic. Fine
for convenience, but since we have all the data right here,
might as well take a more direct approach.
* Remove ill-informed $() calls. This is already a jQuery object
for the method is a jQuery method. Cloning the object first
leads to unexpected side-effects and is simply not neccecary.
* Remove use of .live()
Change-Id: Icfe63a4111026661c53639b72e67a4d4fa3d6ac2