GitLab

Fix compile error with -Wshorten-64-to-32. Image size is new stored as an
offset_t to avoid implicit conversion.

Bug: 881008
Change-Id: I82b12ce17d8368f05d6a5537fd1734ee32b37dbe
Reviewed-on: https://chromium-review.googlesource.com/1213549Reviewed-by: Samuel Huang <huangs@chromium.org>
Commit-Queue: Etienne Pierre-Doray <etiennep@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589938}