Re-add WearNotifications sample to build/sdk.atree am: ccc3c96cd4 am: bf0ff8fe8a am: c610246491 am: d3835b3f8b am: d6325e28ca
am: 36136e4a6f

Change-Id: I4bab2dde1e7e99606bd07da1ac46b636f38b1c6c