Fix SkInternalAtlasTextContext to update advance the flush token after issuing each draw.

This was causing SkAtlasTextTarget:flush() calls beyond the first to skip the uploads of glyphs added to the atlas after the first flush().

Change-Id: I291b88d50629e38914d4b6af21fc25d8a41fbd9d
Reviewed-on: https://skia-review.googlesource.com/77584
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
2 files changed