Require glyph positions in SkAtlasTextTarget::drawText

Change-Id: Idf0977befc8ed4fd9eb3b733db5e945457b2164c
Reviewed-on: https://skia-review.googlesource.com/73701
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
3 files changed