Uniquely identify Slice intents

PendingIntents were being cached because they had the same
targets and would not differentiate on extras - thus all Slice
intents would go to the same destination as the first intent fired.

Adding the data stops the system from caching the intents.

Change-Id: Ifccab72ed482e22750422c5c36aa6d205c20ae3d
Fixes: 77650727
Test: robotests