Migrated MultiSimSettingController

Added subscription manager service support in
MultiSimSettingController. Also added several APIs in
SubscriptionManagerService.

Test: atest SubscriptionManagerServiceTest MultiSimSettingControllerTest
Bug: 239607619
Merged-In: Ibadbf98093a5444f9942ad51384d611c99de15a3
Change-Id: Ibadbf98093a5444f9942ad51384d611c99de15a3

telephony/java/android/telephony/SubscriptionInfo.java

@@ -648,6 +648,15 @@ public class SubscriptionInfo implements Parcelable {
         return mIsOpportunistic;
     }
 
+    /**
+     * @return {@code true} if the subscription is from the actively used SIM.
+     *
+     * @hide
+     */
+    public boolean isActive() {
+        return mSimSlotIndex >= 0 || mType == SubscriptionManager.SUBSCRIPTION_TYPE_REMOTE_SIM;
+    }
+
     /**
      * Used in scenarios where different subscriptions are bundled as a group.
      * It's typically a primary and an opportunistic subscription. (see {@link #isOpportunistic()})