Do not sort named parameters on FunctionNode.

pkg/kernel/lib/analyzer/ast_from_analyzer.dart

Index: pkg/kernel/lib/analyzer/ast_from_analyzer.dart
diff --git a/pkg/kernel/lib/analyzer/ast_from_analyzer.dart b/pkg/kernel/lib/analyzer/ast_from_analyzer.dart
index 63132336881c4c7e7c0c2e45c233d068721ed8ea..9847b5987d91e16fc620094b6d6d34c1e452633c 100644
--- a/pkg/kernel/lib/analyzer/ast_from_analyzer.dart
+++ b/pkg/kernel/lib/analyzer/ast_from_analyzer.dart
@@ -457,9 +457,6 @@ class TypeScope extends ReferenceScope {
           break;
       }
     }
-    if (named.isNotEmpty) {
-      sortAndRemoveDuplicates(named);
-    }
     var returnType = element is ConstructorElement
         ? const ast.VoidType()
         : buildType(element.returnType);
@@ -561,9 +558,6 @@ class ExpressionScope extends TypeScope {
           break;
       }
     }
-    if (named.isNotEmpty) {
-      sortAndRemoveDuplicates(named);
-    }
     return new ast.FunctionNode(buildOptionalFunctionBody(body),
         typeParameters: typeParameters,
         positionalParameters: positional,