notif: Use Zulip's notification sound on Android

Updates: #340

Author: rajveermalviya

android/app/src/main/res/raw/chime3.m4a

@@ -21,7 +21,7 @@ import '../widgets/theme.dart';
 /// Service for configuring our Android "notification channel".
 class NotificationChannelManager {
   @visibleForTesting
-  static const kChannelId = 'messages-1';
+  static const kChannelId = 'messages-2';
 
   /// The vibration pattern we set for notifications.
   // We try to set a vibration pattern that, with the phone in one's pocket,
@@ -30,6 +30,9 @@ class NotificationChannelManager {
   @visibleForTesting
   static final kVibrationPattern = Int64List.fromList([0, 125, 100, 450]);
 
+  @visibleForTesting
+  static const kDefaultSound = RawResourceAndroidNotificationSound('chime3');
+
   /// Create our notification channel, if it doesn't already exist.
   //
   // NOTE when changing anything here: the changes will not take effect
@@ -83,7 +86,7 @@ class NotificationChannelManager {
         importance: Importance.high,
         enableLights: true,
         vibrationPattern: kVibrationPattern,
-        // TODO(#340) sound
+        sound: kDefaultSound,
       ));
   }
 }

lib/notifications/display.dart

@@ -94,7 +94,7 @@ void main() {
         ..groupId.isNull()
         ..importance.equals(Importance.high)
         ..playSound.isTrue()
-        ..sound.isNull()
+        ..sound.equals(NotificationChannelManager.kDefaultSound)
         ..enableVibration.isTrue()
         ..vibrationPattern.isNotNull().deepEquals(
             NotificationChannelManager.kVibrationPattern)