Rm makeRenderTargetContext in favor of deferred version

Change-Id: Ifdf67453607256ba7cdb0837263377bd83907212
Reviewed-on: https://skia-review.googlesource.com/13001
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
24 files changed