Issue 4289. Separate optional positional and named parameters

tests/language/bad_named_parameters_test.dart

Index: tests/language/bad_named_parameters_test.dart
diff --git a/tests/language/bad_named_parameters_test.dart b/tests/language/bad_named_parameters_test.dart
index 937cf05de695080f5d9c5bc4c0f7989a3cb9f710..99a82b84d044f2e2a8aabb5c32564065f42ba73d 100644
--- a/tests/language/bad_named_parameters_test.dart
+++ b/tests/language/bad_named_parameters_test.dart
@@ -6,11 +6,11 @@
 
 class BadNamedParametersTest {
 
-  int f42(int a, [int b = 20, int c = 30]) {
+  int f42(int a, {int b: 20, int c: 30}) {
     return 100*(100*a + b) + c;
   }
 
-  int f52(int a, [int b = 20, int c, int d = 40]) {
+  int f52(int a, {int b: 20, int c, int d: 40}) {
     return 100*(100*(100*a + b) + (c == null ? 0 : c)) + d;
   }