Update pollsters to return counter list

Have pollsters to return the counter list that will be potentially returned.

For bp publisher-counters-frequency

Change-Id: I103f8ed6ad314080d479d4a2053e0df4312c60a3
Signed-off-by: Yunhong, Jiang <yunhong.jiang@intel.com>
Merge "Update pollsters to return counter list"