Reduce dependence on GrSurface's origin field

Unfortunately, GrGPU and its ilk are still using the GrSurface's origin a lot. I will clean that up in a second CL.

Change-Id: Iba729440ce8ea8d24bb7f4e5de55ed576a0f176d
Reviewed-on: https://skia-review.googlesource.com/24700
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
53 files changed