Add listeners to observe role holders changes.

This change adds the ability to add listeners to observe role holder
changes. This will be used by the new role management UI and other
system components that used to put the default app in settings and
observe settings change.

Bug: 110557011
Test: manual
Change-Id: I2a8eb39220081e3be801adb970b60c55ebc297c7
diff --git a/core/java/android/app/role/IRoleManager.aidl b/core/java/android/app/role/IRoleManager.aidl
index 3ca8ec0..4ce0f31 100644
--- a/core/java/android/app/role/IRoleManager.aidl
+++ b/core/java/android/app/role/IRoleManager.aidl
@@ -16,6 +16,7 @@
 
 package android.app.role;
 
+import android.app.role.IOnRoleHoldersChangedListener;
 import android.app.role.IRoleManagerCallback;
 
 /**
@@ -37,6 +38,11 @@
 
     void clearRoleHoldersAsUser(in String roleName, int userId, in IRoleManagerCallback callback);
 
+    void addOnRoleHoldersChangedListenerAsUser(IOnRoleHoldersChangedListener listener, int userId);
+
+    void removeOnRoleHoldersChangedListenerAsUser(IOnRoleHoldersChangedListener listener,
+            int userId);
+
     void setRoleNamesFromController(in List<String> roleNames);
 
     boolean addRoleHolderFromController(in String roleName, in String packageName);