drive: Add ClientContext argument to JobScheduler::RemoveResourceFromDirectory/DeleteResource

To allow requesting these jobs in BACKGROUND context.

BUG=260542
TEST=unit_tests
R=kinaba@chromium.org

Review URL: https://codereview.chromium.org/66273002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@234199 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 234199