Merge branch 'master' into 'master'

run-tests: find current version of aapt in folder rather than in PATH

The Jenkins server did not yet have 19.1.0 build-tools installed yet, so your fixed commits failed to build.  This commit fixes the build:

Not everyone adds the build-tools to their PATH, so this makes it so this script will find aapt in the most recent build-tools version that is installed on the local system.