Add SK_API to SkSurfaceCharacterization

TBR=bsalomon@google.com
Change-Id: I111a6e3eef798d6ad904c17eb536bb64c3801bb2
Reviewed-on: https://skia-review.googlesource.com/118594
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
1 file changed