Fix a bug where updates of offers won't find existing offers

.equals() only work on cross-process Binder instances if casted to
a Binder instance first.

Bug: 184281544
Test: ConnectivityServiceTest. CTS test for this specific issue to come
Merged-In: I3c2563d4ae4e3715d0c6270344ba8f7ef067872f
Merged-In: I7b9e0df21a3cca59659867a75792289ddee2f1d7
Change-Id: I7b9e0df21a3cca59659867a75792289ddee2f1d7
  (cherry-picked from ag/14125149)
2 files changed