Add test for outre GrSurfaceProxy requests

This would've caught the N7 failure in https://skia-review.googlesource.com/c/7738/ (Make blur utils take GrTextureProxies)

Change-Id: I67b56c9d38c14829b2812253c2e3f3e54eb585a5
Reviewed-on: https://skia-review.googlesource.com/7751
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
1 file changed