Fix creating gpu texture from raster image.

In the new world if the GrColorType cannot creating a support backend format
it returns an invalid GrBackendFormat. So we need to check this in our
fallback when uploading raster image to gpu.

Change-Id: Ie69a06ba1a0badb5b7e78965906f09c0413453e2
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/227859
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
1 file changed