Introduce a mechanism for base64 options.

We may wish to pass data to the runner that contains NULs.

Change-Id: Id78dad0ad0b5b6d0537481c818e3febdf1740cc9
Reviewed-on: https://boringssl-review.googlesource.com/1603
Reviewed-by: Adam Langley <agl@google.com>
2 files changed