Update GrTextureStripAtlas for DDLs (take 2)

Change-Id: I4a3f71ffe4a14785e7befddc378929cf4dcf7d8e
Reviewed-on: https://skia-review.googlesource.com/145150
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
11 files changed