This works, but there's enough shared codepaths that it's worth a test to
ensure it stays that way.
Change-Id: I5d5a729811e35832170322957258304213204e3b
Reviewed-on: https://boringssl-review.googlesource.com/1155
Reviewed-by: Adam Langley <agl@google.com>
Initial fork from f2d678e6e89b6508147086610e985d4e8416e867 (1.0.2 beta).
(This change contains substantial changes from the original and
effectively starts a new history.)