resourceloader: Un-deprecate makeLoaderConditionalScript()

resourceloader: Un-deprecate makeLoaderConditionalScript()

It was deprecated to encourage callers to use makeInlineScript()
instead, because before makeInlineScript() was introduced, callers
would often manually wrap it in a <script> tag, which we don't want
because 1) We want de-duplication through WrappedString and 2)
callers sometimes forget to use Html.php methods that ensure
proper escaping as-needed.

However, there is still use in getting thet wrapped script without
also the wrapped HTML script tag. Namely, for use in http responses
that produce JavaScript, rather than HTML, where there cannot be
an HTML script tag.

There is at least one such caller (in SpecialJavaScriptTest) and
it's fine for there to be others.

Change-Id: Icfc285e12293c76dc68a220deb6816e32b058209