Revert of add a ClassID function to GrBatch (patchset #5 id:80001 of https://codereview.chromium.org/1352813003/ )

Reason for revert:
Speculative revert to unblock DEPS roll

Original issue's description:
> add a ClassID function to GrBatch
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/4078d529e9e199eea13456db7bf3a63a104ab5b9
>
> Committed: https://skia.googlesource.com/skia/+/eb44d53cf96a7eaf103a98d76079ce1f5495e343

TBR=robertphillips@google.com,bsalomon@google.com,joshualitt@google.com,joshualitt@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1353043002
34 files changed