Regenerate signatures automatically in x509_util_unittest.c, and create helper functions for future tests.

Change-Id: I36a0bdc94d097a6005b8e07100e8779f10f35aff
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1531283
Commit-Queue: Jesse Selover <[email protected]>
Reviewed-by: David Benjamin <[email protected]>
Cr-Commit-Position: refs/heads/master@{#642614}
5 files changed