Stop profiling on uncaught exception.

When "handling" an uncaught exception, make an attempt to stop
profiling. In case profiling was active, this will avoid losing
the profiling buffer.

This change is required as a base in order for
https://android-review.googlesource.com/#/c/249721/
to merge cleanly.

(Cherry picked from commit 4c79fea9)
Bug: 26291225
Change-Id: I35f352e5f28eafe4702da9eae587c3b65c360b3a