Add a factory to any GrOp-derived class that lacked one

All GrOp-derived classes are going to have allocate their memory in a GrMemoryPool.

Change-Id: Ifa410b05eecd9b68c39dcc15dd4298d617204c13
Reviewed-on: https://skia-review.googlesource.com/132828
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
11 files changed