Merge "Revert "Revert "Adding unit tests for exception classes""" am: fab4288df5 am: ce1ff64b87 am: 1430f88d16

Original change: https://android-review.googlesource.com/c/platform/libcore/+/1697668

Change-Id: I7dd3fc608009ebf293f3a7c5929df56e7aaf3317