Accept processor test seed from command line

Also adds support for uint32_t CLI flags, parsed as octal, hex, or dec.

Bug: skia:
Change-Id: I87112beb6506a65d6f541c7ca4cfb38641d55aa5
Reviewed-on: https://skia-review.googlesource.com/158040
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
3 files changed