Fix NPE

Test: NotificationChannelGroupTest
Test: view notification settings for an app that doesn't use groups
Fixes: 244574602
Bug: 241764350
Bug: 241764340
Bug: 241764135
Bug: 242702935
Bug: 242703118
Bug: 242703202
Bug: 242702851
Bug: 242703217
Bug: 242703556
Change-Id: I9c681106f6d645e62b0e44903d40aa523fee0e95
(cherry picked from commit 6f02c07176d0fa4d6985c8f2200ccf49a1657d1c)

2 files changed, 27 insertions, 3 deletions

diff --git a/core/java/android/app/NotificationChannelGroup.java b/core/java/android/app/NotificationChannelGroup.java
index c194a2844bd5..39e48443f1ff 100644
--- a/core/java/android/app/NotificationChannelGroup.java
+++ b/core/java/android/app/NotificationChannelGroup.java
@@ -95,8 +95,11 @@ public final class NotificationChannelGroup implements Parcelable {
         } else {
             mId = null;
         }
-        mName = TextUtils.CHAR_SEQUENCE_CREATOR.createFromParcel(in);
-        mName = getTrimmedString(mName.toString());
+        if (in.readByte() != 0) {
+            mName = getTrimmedString(in.readString());
+        } else {
+            mName = "";
+        }
         if (in.readByte() != 0) {
             mDescription = getTrimmedString(in.readString());
         } else {
@@ -122,7 +125,12 @@ public final class NotificationChannelGroup implements Parcelable {
         } else {
             dest.writeByte((byte) 0);
         }
-        TextUtils.writeToParcel(mName.toString(), dest, flags);
+        if (mName != null) {
+            dest.writeByte((byte) 1);
+            dest.writeString(mName.toString());
+        } else {
+            dest.writeByte((byte) 0);
+        }
         if (mDescription != null) {
             dest.writeByte((byte) 1);
             dest.writeString(mDescription);
diff --git a/core/tests/coretests/src/android/app/NotificationChannelGroupTest.java b/core/tests/coretests/src/android/app/NotificationChannelGroupTest.java
index 2a3da05eabb3..625c66a4c60e 100644
--- a/core/tests/coretests/src/android/app/NotificationChannelGroupTest.java
+++ b/core/tests/coretests/src/android/app/NotificationChannelGroupTest.java
@@ -17,9 +17,11 @@
 package android.app;
 
 import static junit.framework.TestCase.assertEquals;
+import static junit.framework.TestCase.assertTrue;
 
 import android.os.Parcel;
 import android.test.AndroidTestCase;
+import android.text.TextUtils;
 
 import androidx.test.filters.SmallTest;
 import androidx.test.runner.AndroidJUnit4;
@@ -70,4 +72,18 @@ public class NotificationChannelGroupTest {
         assertEquals(NotificationChannelGroup.MAX_TEXT_LENGTH,
                 fromParcel.getDescription().length());
     }
+
+    @Test
+    public void testNullableFields() {
+        NotificationChannelGroup group = new NotificationChannelGroup("my_group_01", null);
+
+        Parcel parcel = Parcel.obtain();
+        group.writeToParcel(parcel, 0);
+        parcel.setDataPosition(0);
+
+        NotificationChannelGroup fromParcel =
+                NotificationChannelGroup.CREATOR.createFromParcel(parcel);
+        assertEquals(group.getId(), fromParcel.getId());
+        assertTrue(TextUtils.isEmpty(fromParcel.getName()));
+    }
 }