This adds a script which runs the end2end_tests, captures a wire trace,
and then minimizes the corpus with the fuzzer. Minimizing the corpus
requires libfuzzer, so this only works in a Chromium checkout.
Unseeded, the fuzzer starts with coverage of about 600 features.
Using a seed corpus captured from the tests, the fuzzer quickly
increases coverage to about 10,000 features.
Change-Id: I8d0db5121745bd5ee4a350cf46fb37cfa434e3dc
Bug: dawn:295
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/14242
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>