Should only call the new callback

Also check null on the service side

Bug: 325544756
Test: atest WifiManagerTest
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:0ecd3aea171d62e82a234698114d5ad8df1074ac)
Merged-In: I4e1c0d8dce4fd6d1be51653f776843a66cb7ec85
Change-Id: I4e1c0d8dce4fd6d1be51653f776843a66cb7ec85
3 files changed