The stated purpose of separating libs and gwt_libs is to avoid
incorrect versions of classes used elsewhere in Gerrit (e.g. servlet
API 3.0 instead of 3.1). But we were iterating through gwt_libs first,
so this wasn't actually working. Swap the order.
Also change the prefix check for GWT deps to a contains check, as buck
audit at some point started returning absolute paths to jars.
Change-Id: Ic372b6bfaca5a8a1c1b9cc32aaf868a86a91c6ef
004bf2a928