Merge "DO NOT MERGE: Bump CTS and CTS Verifier to 6.0_r15" into marshmallow-cts-dev am: 1d8c12aa80  -s ours am: 7f203e5d1f  -s ours am: 1795ae05dd
am: e86f75e926

Change-Id: I9263143f4533c2bba741ab226a883a1872bf758b