From 35e99ea8ef62482b81c0ce043fcd5acc96ad257d Mon Sep 17 00:00:00 2001
From: Jeremy Klein <jlklein@google.com>
Date: Sat, 12 Mar 2016 16:29:54 -0800
Subject: [PATCH] Add a null check for the OnStartTetheringCallback.

This avoids a NullPointerException when trying to call the callback
and gives a more readable error message.

Change-Id: Id0353ef541c76efcb4a9a12c082e1b6ec9389f02
---
 core/java/android/net/ConnectivityManager.java | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/core/java/android/net/ConnectivityManager.java b/core/java/android/net/ConnectivityManager.java
index 5f1043ba8f..ab9f9fb47e 100644
--- a/core/java/android/net/ConnectivityManager.java
+++ b/core/java/android/net/ConnectivityManager.java
@@ -1987,6 +1987,8 @@ public class ConnectivityManager {
     @SystemApi
     public void startTethering(int type, boolean showProvisioningUi,
             final OnStartTetheringCallback callback, Handler handler) {
+        checkNotNull(callback, "OnStartTetheringCallback cannot be null.");
+
         ResultReceiver wrappedCallback = new ResultReceiver(handler) {
             @Override
             protected void onReceiveResult(int resultCode, Bundle resultData) {
@@ -1997,6 +1999,7 @@ public class ConnectivityManager {
                 }
             }
         };
+
         try {
             mService.startTethering(type, wrappedCallback, showProvisioningUi);
         } catch (RemoteException e) {