deps: Update pigeon to latest

Changelog:
  https://pub.dev/packages/pigeon/changelog

The only breaking change is:

  Limits the number of total custom types to 126.

  If more than 126 custom types are needed, consider breaking up
  your definition files.

Which definitely isn't a problem for us!

The changes all look pretty innocuous; but just to confirm, I fired
up the app (as a release build) and tested end-to-end that
notifications still appear.  As usual I tested it while the app was
in the foreground, in the background, and not running.

Author: gnprice

android/app/src/main/kotlin/com/zulip/flutter/Notifications.g.kt

@@ -1,4 +1,4 @@
-// Autogenerated from Pigeon (v19.0.2), do not edit directly.
+// Autogenerated from Pigeon (v20.0.1), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 @file:Suppress("UNCHECKED_CAST", "ArrayInDataClass")
 
@@ -75,17 +75,17 @@ data class PendingIntent (
     }
   }
   fun toList(): List<Any?> {
-    return listOf<Any?>(
+    return listOf(
       requestCode,
       intentPayload,
       flags,
     )
   }
 }
-private object AndroidNotificationHostApiCodec : StandardMessageCodec() {
+private object NotificationsPigeonCodec : StandardMessageCodec() {
   override fun readValueOfType(type: Byte, buffer: ByteBuffer): Any? {
     return when (type) {
-      128.toByte() -> {
+      129.toByte() -> {
         return (readValue(buffer) as? List<Any?>)?.let {
           PendingIntent.fromList(it)
         }
@@ -96,7 +96,7 @@ private object AndroidNotificationHostApiCodec : StandardMessageCodec() {
   override fun writeValue(stream: ByteArrayOutputStream, value: Any?)   {
     when (value) {
       is PendingIntent -> {
-        stream.write(128)
+        stream.write(129)
         writeValue(stream, value.toList())
       }
       else -> super.writeValue(stream, value)
@@ -130,7 +130,7 @@ interface AndroidNotificationHostApi {
   companion object {
     /** The codec used by AndroidNotificationHostApi. */
     val codec: MessageCodec<Any?> by lazy {
-      AndroidNotificationHostApiCodec
+      NotificationsPigeonCodec
     }
     /** Sets up an instance of `AndroidNotificationHostApi` to handle messages through the `binaryMessenger`. */
     @JvmOverloads
@@ -152,7 +152,7 @@ interface AndroidNotificationHostApi {
             val smallIconResourceNameArg = args[8] as String?
             val wrapped: List<Any?> = try {
               api.notify(tagArg, idArg, channelIdArg, colorArg, contentIntentArg, contentTextArg, contentTitleArg, extrasArg, smallIconResourceNameArg)
-              listOf<Any?>(null)
+              listOf(null)
             } catch (exception: Throwable) {
               wrapError(exception)
             }

lib/host/android_notifications.g.dart

@@ -1,4 +1,4 @@
-// Autogenerated from Pigeon (v19.0.2), do not edit directly.
+// Autogenerated from Pigeon (v20.0.1), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 // ignore_for_file: public_member_api_docs, non_constant_identifier_names, avoid_as, unused_import, unnecessary_parenthesis, prefer_null_aware_operators, omit_local_variable_types, unused_shown_name, unnecessary_import, no_leading_underscores_for_local_identifiers
 
@@ -53,12 +53,13 @@ class PendingIntent {
   }
 }
 
-class _AndroidNotificationHostApiCodec extends StandardMessageCodec {
-  const _AndroidNotificationHostApiCodec();
+
+class _PigeonCodec extends StandardMessageCodec {
+  const _PigeonCodec();
   @override
   void writeValue(WriteBuffer buffer, Object? value) {
     if (value is PendingIntent) {
-      buffer.putUint8(128);
+      buffer.putUint8(129);
       writeValue(buffer, value.encode());
     } else {
       super.writeValue(buffer, value);
@@ -68,7 +69,7 @@ class _AndroidNotificationHostApiCodec extends StandardMessageCodec {
   @override
   Object? readValueOfType(int type, ReadBuffer buffer) {
     switch (type) {
-      case 128: 
+      case 129: 
         return PendingIntent.decode(readValue(buffer)!);
       default:
         return super.readValueOfType(type, buffer);
@@ -85,7 +86,7 @@ class AndroidNotificationHostApi {
         __pigeon_messageChannelSuffix = messageChannelSuffix.isNotEmpty ? '.$messageChannelSuffix' : '';
   final BinaryMessenger? __pigeon_binaryMessenger;
 
-  static const MessageCodec<Object?> pigeonChannelCodec = _AndroidNotificationHostApiCodec();
+  static const MessageCodec<Object?> pigeonChannelCodec = _PigeonCodec();
 
   final String __pigeon_messageChannelSuffix;
 

pubspec.lock

@@ -845,10 +845,10 @@ packages:
     dependency: "direct dev"
     description:
       name: pigeon
-      sha256: "5710a43ab5e7564533758ef2b0b02cd51b15080183603a4f8f11515fe0bbc8a4"
+      sha256: "012cdc56c09fc901fd44e44cd4ada9a859a839f55e0b0365f1ed683fe0072404"
       url: "https://pub.dev"
     source: hosted
-    version: "19.0.2"
+    version: "20.0.1"
   platform:
     dependency: transitive
     description:

pubspec.yaml

@@ -82,7 +82,7 @@ dev_dependencies:
   fake_async: ^1.3.1
   flutter_lints: ^4.0.0
   json_serializable: ^6.5.4
-  pigeon: ^19.0.0
+  pigeon: ^20.0.1
   plugin_platform_interface: ^2.1.8
   stack_trace: ^1.11.1
   test: ^1.23.1