In vulkan align data in buffer when copying to image

BUG=skia:

Change-Id: If99ba2797dfca547ce98cd9c1a1f1c234cf8791e
Reviewed-on: https://skia-review.googlesource.com/10027
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
1 file changed