Move resourceProvider accessor to GrContextPriv (take 2)

TBR=bsalomon@google.com
Change-Id: I3fd46ebfad0d04b8a2bfa6190f81308f3a6be620
Reviewed-on: https://skia-review.googlesource.com/95121
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
41 files changed