Merge "MediaSessionService: Fix NPE when startup" into rvc-dev am: b8b17a1f5f

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11882408

Change-Id: I9d181b8041725d37a3b589a3956a26023e416132

services/core/java/com/android/server/media/MediaButtonReceiverHolder.java

@@ -85,6 +85,9 @@ final class MediaButtonReceiverHolder {
             return null;
         }
         ComponentName componentName = ComponentName.unflattenFromString(tokens[0]);
+        if (componentName == null) {
+            return null;
+        }
         int userId = Integer.parseInt(tokens[1]);
         // Guess component type if the OS version is updated from the older version.
         int componentType = (tokens.length == 3)