Remove unused GrObjectMemoryPool

Change-Id: I8d37dfa3a5f0af4741eb6f1c10e13065d20b0ccb
Reviewed-on: https://skia-review.googlesource.com/132829
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
2 files changed