Move makeDeferredRenderTargetContext calls to factory on RTC.

Change-Id: Iaa8f5829d9f8650ff27a60f75fb2216f016ab85e
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/262058
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
54 files changed