Cache getDefaultSmsSubscriptionId Binder calls

Use PropertyInvalidatedCache to avoid redundant
calls to SubscriptionController.getDefaultSmsSubscriptionId.
Bug: 151953109
Test: Verified cache operated correctly when phone process is killed.
Test: atest SubscriptionControllerTest
Test: atest android.telephony.cts.SubscriptionManagerTest

Merged-In: Iadb6a42b256013021903f75ed72bb5f046bfa2cc
Change-Id: Iadb6a42b256013021903f75ed72bb5f046bfa2cc