GitLab

This is preparation to start returning DriveIntegrationService always from
DriveIntegrationServiceFactory::{Get,Find}ForProfile.

BUG=284972
TEST=Ran unit_tests
R=kinaba@chromium.org, satorux@chromium.org

Review URL: https://codereview.chromium.org/23523022

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@221356 0039d316-1c4b-4281-b951-d872f2087c98