GitLab

When the user is signed in and syncing, the signin-allowed
toggle is now disabled.

Note: This CL is adapted from crrev.com/c/1273517 and
removes the hint, i.e. there are no string changes here.

Bug: 892745
Change-Id: I1778115390518860fca4b4f11588d5ca7c7b9210
Reviewed-on: https://chromium-review.googlesource.com/c/1275849Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Commit-Queue: Thomas Tangl <tangltom@chromium.org>
Cr-Commit-Position: refs/heads/master@{#598901}