Add --traceMatch argument to filter tracing categories

Bug: skia:
Change-Id: I1449f0f4d7d9ab6225d98c601eafa7461a2a7dde
Reviewed-on: https://skia-review.googlesource.com/27120
Commit-Queue: Brian Osman <brianosman@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
1 file changed