Add Nullable to MediaHTTPService's mCookies.

Bug: 29321867
Test: manually tested with ndk sample native-audio
Change-Id: Ic30fe7c28db0111ee5bcb91b037b7c4536dcfd06
diff --git a/media/java/android/media/MediaHTTPService.java b/media/java/android/media/MediaHTTPService.java
index 3a0e58a..98517d1 100644
--- a/media/java/android/media/MediaHTTPService.java
+++ b/media/java/android/media/MediaHTTPService.java
@@ -16,6 +16,7 @@
 
 package android.media;
 
+import android.annotation.Nullable;
 import android.os.IBinder;
 import android.util.Log;
 
@@ -28,10 +29,10 @@
 /** @hide */
 public class MediaHTTPService extends IMediaHTTPService.Stub {
     private static final String TAG = "MediaHTTPService";
-    private List<HttpCookie> mCookies;
+    @Nullable private List<HttpCookie> mCookies;
     private Boolean mCookieStoreInitialized = new Boolean(false);
 
-    public MediaHTTPService(List<HttpCookie> cookies) {
+    public MediaHTTPService(@Nullable List<HttpCookie> cookies) {
         mCookies = cookies;
         Log.v(TAG, "MediaHTTPService(" + this + "): Cookies: " + cookies);
     }