Remove unused GrGpuResourceRef and GrTGpuResourceRef

Change-Id: I8b4b323549f51e4601ccb6612f65d354e163e93c
Reviewed-on: https://skia-review.googlesource.com/144504
Auto-Submit: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
9 files changed