Add quick-fix to convert child: to children:

pkg/analysis_server/lib/src/services/correction/fix.dart

Index: pkg/analysis_server/lib/src/services/correction/fix.dart
diff --git a/pkg/analysis_server/lib/src/services/correction/fix.dart b/pkg/analysis_server/lib/src/services/correction/fix.dart
index 8053d741f3ea0a9a0a82284d48b0d1b1e7bf3d4b..fc6dcd5785a058a8a16533c69a59f3f55041b694 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix.dart
@@ -105,6 +105,7 @@ bool hasFix(ErrorCode errorCode) =>
     errorCode == StaticTypeWarningCode.UNDEFINED_GETTER ||
     errorCode == StaticTypeWarningCode.UNDEFINED_METHOD ||
     errorCode == StaticTypeWarningCode.UNDEFINED_SETTER ||
+    errorCode == CompileTimeErrorCode.UNDEFINED_NAMED_PARAMETER ||
     (errorCode is LintCode &&
         (errorCode.name == LintNames.annotate_overrides ||
             errorCode.name == LintNames.unnecessary_brace_in_string_interp));
@@ -137,6 +138,8 @@ class DartFixKind {
       'CHANGE_TO_STATIC_ACCESS', 50, "Change access to static using '{0}'");
   static const CHANGE_TYPE_ANNOTATION = const FixKind(
       'CHANGE_TYPE_ANNOTATION', 50, "Change '{0}' to '{1}' type annotation");
+  static const CONVERT_FLUTTER_CHILD =
+      const FixKind('CONVERT_FLUTTER_CHILD', 50, "Convert to children:");
   static const CREATE_CLASS =
       const FixKind('CREATE_CLASS', 50, "Create class '{0}'");
   static const CREATE_CONSTRUCTOR =