Scheduler: enable scheduler hint to pass the group name

Commit ea6d8403bdc3c1d3ede87a2ed1c8740420c32080 partially
dealt with the problem. The actual scheduling would fail when
the group name was passed.

Change-Id: I668621770e59504164af9a2e861a59e900300bba
Closes-bug: #1303360
(cherry picked from commit a2059b67b207d908b1c65c78dd806b1f5e79582d)