upgrade flutter

packages/flutter_mozilla_components/android/src/main/kotlin/eu/weblibre/flutter_mozilla_components/pigeons/Gecko.g.kt

@@ -1,4 +1,4 @@
-// Autogenerated from Pigeon (v26.3.2), do not edit directly.
+// Autogenerated from Pigeon (v26.3.4), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 @file:Suppress("UNCHECKED_CAST", "ArrayInDataClass")
 
@@ -193,7 +193,7 @@ class FlutterError (
   val code: String,
   override val message: String? = null,
   val details: Any? = null
-) : Throwable()
+) : RuntimeException()
 
 /** Indicates what location the tabs should be restored at */
 enum class RestoreLocation(val raw: Int) {

packages/flutter_mozilla_components/pubspec.yaml

@@ -18,7 +18,7 @@ dev_dependencies:
   flutter_test:
     sdk: flutter
   lint: ^2.8.0
-  pigeon: ^26.3.2
+  pigeon: ^26.3.4
 
 # For information on the generic Dart part of this file, see the
 # following page: https://dart.dev/tools/pub/pubspec