Unbundle ART API from android-non-updatable

Stop tracking the ART APIs in the non-updatable current.txt, and
instead add in the txt/srcjar/jar files produced by the art module's
java_sdk_library.

Bug: 173606718
Test: manual last_released check of merged api txt (b/174847574 to
      automate)
Change-Id: I446a381f2b364a114ce391b99a13742d6769f14d