DO NOT MERGE. Cherry pick 'Add logging of test events.'

With this comment, logs dumped to logcat during a test run will be
roughly equivalent to InstrumentationTestRunner.

Change-Id: I7c1ce776aaec3779f531f95afa5275bbbe7d96a7
(cherry picked from commit d9eb347ae059e1efbe3d94874ee88db5bb1d9b90)
2 files changed