We already did this, but it was rather convoluted with lots of
if/elseif sequences checking all the possible values.
Remove this logic from ResourceLoaderStartUpModule. Simplying it
simply create the array and pass it to ResourceLoader::makeLoaderRegisterScript.
In makeLoaderRegisterScript, we apply a filter to the array(s) that
trim empty values.
While at it:
* As with other registration properties' default values (like for dependencies,
group, and skip) also use 'null' for the default value of 'source'.
The mediawiki.js client was already compatible with this, and the server omitted
it if it was the last value in the list. But in all other cases it explicitly
outputs "local". Use null instead of simplicity sake. This also gains us a
few characters in the output, and a relatively larger win after gzip since
there's lots more re-using of "null".
* Remove stray casting of $version to int. This only happened in case of
registering a single module (which don't do anywhere), and is redundant.
Change-Id: I1f321e7b8bd3b5cffc550b51169957a3da9b971d
c0c221bfe4