Fix GcmApiTest with NavigationLoaderOnUI enabled

ProfileSyncService may not be created if a command line flag turns off
sync. In this case, ProfileSyncServiceFactory::GetForProfile returns
null and crashes when IsSyncFeatureEnabled is called.

Bug: 978617
Change-Id: Idb381a82008065427d67d87583f56eca9d1e9606
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1715094
Commit-Queue: Clark DuVall <cduvall@chromium.org>
Reviewed-by: Boris Sazonov <bsazonov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#680137}
2 files changed