GitLab

Previously the image annotation code only handled OCR results
from the server. Now that captions and labels are hooked up,
expose those image annotation strings too.

Bug: 905419
Change-Id: I88542054c49ba252d5bc13d0024054059b8f5123
Reviewed-on: https://chromium-review.googlesource.com/c/1492475Reviewed-by: Katie Dektar <katie@chromium.org>
Commit-Queue: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#636279}