Have mip status match surface when snapping image from wrapped object

Also fixes some bugs involved with creating mipped SkSurfaces.

Bug: skia:
Change-Id: I6e0109000eadd2bdee4a907d3ee2231104528165
Reviewed-on: https://skia-review.googlesource.com/65063
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
15 files changed