Rebuild proguard.jar with ant/gradle support.

By setting ANT_HOME and GRADLE_HOME in build/build.sh.

Bug: 26274804
Change-Id: Iad81e3f81759ebb3461bfedfc2fed0b0229acca8
(cherry-pick from commit eedc65a59bf96c2075b7feecae6c5fd1d3713e9e)
3 files changed