Pin libraries needed by vogar tool to java 1.7

vogar still uses javac/dx by default. dx does not
handle v52 class files. The default java version
is going to switch to 1.8. This change pins the
targets need by vogar to 1.7.

Bug: 26753820
Bug: 27310428
(cherry picked from commit d2d6de39e231863b8d91a0025f45637aaf400e3e)

Change-Id: Ifab6ba8a23932b83d7aa41c4c5aef4d339db5265
1 file changed