Update update_rs_prebuilts.sh to explicitly make support lib jar

Bug: 27338966

  - Previously we were using dx to generate jar for support lib.
  - Since JACK supports generating jar files directly, update the
    script to do the right thing.

Change-Id: If3a4f439b50be19695d0cec81fe4c5c4254a1b7f
(cherry picked from commit a354a8e0c546df15759accfec1c568c866efba1e)
1 file changed