Merge "Copy lists to ensure deep immutability in RoutingSessionInfo"

media/java/android/media/RoutingSessionInfo.java

@@ -23,7 +23,6 @@ import android.os.Bundle;
 import android.os.Parcel;
 import android.os.Parcelable;
 import android.text.TextUtils;
-import android.util.Log;
 
 import com.android.internal.util.Preconditions;
 
@@ -117,6 +116,8 @@ public final class RoutingSessionInfo implements Parcelable {
         mProviderId = src.readString();
 
         mSelectedRoutes = ensureList(src.createStringArrayList());
+        Preconditions.checkArgument(!mSelectedRoutes.isEmpty());
+
         mSelectableRoutes = ensureList(src.createStringArrayList());
         mDeselectableRoutes = ensureList(src.createStringArrayList());
         mTransferableRoutes = ensureList(src.createStringArrayList());
@@ -416,15 +417,21 @@ public final class RoutingSessionInfo implements Parcelable {
         return result.toString();
     }
 
+    /**
+     * Provides a new list with unique route IDs if {@link #mProviderId} is set, or the original IDs
+     * otherwise.
+     *
+     * @param routeIds list of route IDs to convert
+     * @return new list with unique IDs or original IDs
+     */
+
+    @NonNull
     private List<String> convertToUniqueRouteIds(@NonNull List<String> routeIds) {
-        if (routeIds == null) {
-            Log.w(TAG, "routeIds is null. Returning an empty list");
-            return Collections.emptyList();
-        }
+        Objects.requireNonNull(routeIds, "RouteIds cannot be null.");
 
         // mProviderId can be null if not set. Return the original list for this case.
         if (TextUtils.isEmpty(mProviderId)) {
-            return routeIds;
+            return new ArrayList<>(routeIds);
         }
 
         List<String> result = new ArrayList<>();