Merge branch 'for-3.16' into test-merge-for-3.16

Multiple conflicts due to the following two commits in cgroup branch.

  ec903c0c858e ("cgroup: rename css_tryget*() to css_tryget_online*()")
  5c9d535b893f ("cgroup: remove css_parent(")

Both commits, in themselves, are trivial and the conflicts can be
resolved by taking the code from the master side and then applying the
necessary renames.

Signed-off-by: Tejun Heo <tj@kernel.org>