Rename GrBatch to GrOp

Change-Id: I27b6324f8040899fafeda23ca524bc54a4dbf090
Reviewed-on: https://skia-review.googlesource.com/5392
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
66 files changed