drawText Cleanup, part 4

Change-Id: I2b48b6f507fe567cf44836c8755871c2a2f61ec0
Reviewed-on: https://skia-review.googlesource.com/c/182220
Auto-Submit: Hal Canary <halcanary@google.com>
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Mike Reed <reed@google.com>