pigeon [nfc]: Rename pigeon file to notification -> android_notifications

Author: rajveermalviya

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

@@ -381,7 +381,7 @@ data class StoredNotificationSound (
     )
   }
 }
-private open class NotificationsPigeonCodec : StandardMessageCodec() {
+private open class AndroidNotificationsPigeonCodec : StandardMessageCodec() {
   override fun readValueOfType(type: Byte, buffer: ByteBuffer): Any? {
     return when (type) {
       129.toByte() -> {
@@ -589,7 +589,7 @@ interface AndroidNotificationHostApi {
   companion object {
     /** The codec used by AndroidNotificationHostApi. */
     val codec: MessageCodec<Any?> by lazy {
-      NotificationsPigeonCodec()
+      AndroidNotificationsPigeonCodec()
     }
     /** Sets up an instance of `AndroidNotificationHostApi` to handle messages through the `binaryMessenger`. */
     @JvmOverloads

pigeon/notifications.dart renamed to pigeon/android_notifications.dart

@@ -4,7 +4,7 @@ import 'package:pigeon/pigeon.dart';
 // run `tools/check pigeon --fix`.
 @ConfigurePigeon(PigeonOptions(
   dartOut: 'lib/host/android_notifications.g.dart',
-  kotlinOut: 'android/app/src/main/kotlin/com/zulip/flutter/Notifications.g.kt',
+  kotlinOut: 'android/app/src/main/kotlin/com/zulip/flutter/AndroidNotifications.g.kt',
   kotlinOptions: KotlinOptions(package: 'com.zulip.flutter'),
 ))