GitLab

These started getting discarded when we switched to r8.
Two of these were previously fixed by adding @UsedByReflection,
but it seems safer to just keep all fragment constructors and
does not seem to keep anything unused.

Bug: 983904

Change-Id: I60bbc5a32dc49732aebd8048d674375cbc133f7e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1703595
Commit-Queue: Andrew Grieve <agrieve@chromium.org>
Reviewed-by: Boris Sazonov <bsazonov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#678277}