Simplify some Vulkan compressed texture setup.

onWrapCompressedBackendTexture and onCreateCompressedBackendTexture can
use their non-compressed equivalents, with the addition of a read-only
parameter.

Change-Id: Ia9955fb378597e9460b0a439036154f3952e2057
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/301977
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
Auto-Submit: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
1 file changed