Don't return null at Phone.getIccCard.

Phone.getIccCard used to always return a non-null object.
But getUiccProfile() can return null if SIM card is not present.
For backward compatibility consideration, we return a dummy
object instead of null.

Bug: 74608255
Test: unittest
Change-Id: Ic985e9e24c5b7fc0185d5d555a66db3e6a44c44c
Merged-In: Ic985e9e24c5b7fc0185d5d555a66db3e6a44c44c