Copy benchmark names, which may be transient strings

Bug: skia:
Change-Id: Ic4073aa17a04e8b400cc4a9db9a0669ee4a5c894
Reviewed-on: https://skia-review.googlesource.com/44203
Commit-Queue: Brian Osman <brianosman@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
1 file changed