Throw for showSystemOutputSwitcher() call from privileged router

Previously, a call from a privileged router would have thrown a Security
Exception from MediaRouterService in a similar way to ag/24264289.

Bug: 192657812
Test: atest MediaRouter2Test SystemMediaRouter2Test
Change-Id: I32e27d5dfdd07f1d6dc334ab5e8fd02817006ecf

1 files changed, 21 insertions, 8 deletions

diff --git a/media/java/android/media/MediaRouter2.java b/media/java/android/media/MediaRouter2.java
index 6b67d1452deb..1baae4abeb68 100644
--- a/media/java/android/media/MediaRouter2.java
+++ b/media/java/android/media/MediaRouter2.java
@@ -439,14 +439,7 @@ public final class MediaRouter2 {
      * call is ignored because the app is in the background.
      */
     public boolean showSystemOutputSwitcher() {
-        synchronized (mLock) {
-            try {
-                return mMediaRouterService.showMediaOutputSwitcher(mImpl.getPackageName());
-            } catch (RemoteException ex) {
-                ex.rethrowFromSystemServer();
-            }
-        }
-        return false;
+        return mImpl.showSystemOutputSwitcher();
     }
 
     /**
@@ -1950,6 +1943,8 @@ public final class MediaRouter2 {
 
         void setRouteListingPreference(@Nullable RouteListingPreference preference);
 
+        boolean showSystemOutputSwitcher();
+
         List<MediaRoute2Info> getAllRoutes();
 
         void setOnGetControllerHintsListener(OnGetControllerHintsListener listener);
@@ -2096,6 +2091,12 @@ public final class MediaRouter2 {
                     "RouteListingPreference cannot be set by a privileged MediaRouter2 instance.");
         }
 
+        @Override
+        public boolean showSystemOutputSwitcher() {
+            throw new UnsupportedOperationException(
+                    "Cannot show system output switcher from a privileged router.");
+        }
+
         /** Gets the list of all discovered routes. */
         @Override
         public List<MediaRoute2Info> getAllRoutes() {
@@ -2908,6 +2909,18 @@ public final class MediaRouter2 {
             }
         }
 
+        @Override
+        public boolean showSystemOutputSwitcher() {
+            synchronized (mLock) {
+                try {
+                    return mMediaRouterService.showMediaOutputSwitcher(mImpl.getPackageName());
+                } catch (RemoteException ex) {
+                    ex.rethrowFromSystemServer();
+                }
+            }
+            return false;
+        }
+
         /**
          * Returns {@link Collections#emptyList()}. Local routes can only access routes related to
          * their {@link RouteDiscoveryPreference} through {@link #getRoutes()}.