Require copy as draws for vulkan cross context image support

Bug: skia:
Change-Id: I0eb5039146278f88b7a869c8c19d5f84d5857529
Reviewed-on: https://skia-review.googlesource.com/17108
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
1 file changed