Add three more GrFragmentProcessor::clone() implementations

ArithmeticFP
GrRectBlurEffect
GrRRectBlurEffect

Change-Id: I741f3125e5b3753b3afb0a5acd56611dec8b3d22
Reviewed-on: https://skia-review.googlesource.com/26425
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
2 files changed