Fix some issues after introducing NamedType.

testcases/type-propagation/named_parameters.baseline.txt

Index: testcases/type-propagation/named_parameters.baseline.txt
diff --git a/testcases/type-propagation/named_parameters.baseline.txt b/testcases/type-propagation/named_parameters.baseline.txt
index fe5704375df9f12d7aa07c054653be2c88f2987a..81775b5e308b682fb9f741ec880a337503a8d421 100644
--- a/testcases/type-propagation/named_parameters.baseline.txt
+++ b/testcases/type-propagation/named_parameters.baseline.txt
@@ -8,7 +8,10 @@ class Superclass extends core::Object {
     ;
   method foo({dynamic/Null alpha, dynamic/Null beta}) → dynamic/Null {}
   method bar({dynamic/Null alpha, dynamic/Null beta}) → dynamic/Null {}
-  method namedCallback(({alpha: dynamic, beta: dynamic}) → dynamic/Nothing callback) → dynamic/Null {}
+  method namedCallback(({alpha: core::String, beta: core::int}) → dynamic/Nothing callback) → dynamic/Null {
+    callback.call(alpha: "one", beta: 2);
+    callback.call(beta: 1, alpha: "two");
+  }
 }
 class Subclass extends self::Superclass {
   constructor •() → void
@@ -16,7 +19,7 @@ class Subclass extends self::Superclass {
     ;
   method foo({dynamic/core::int* {null,int} alpha, dynamic/core::int* {null,int} beta}) → dynamic/Null {}
   method bar({dynamic/Null alpha, dynamic/Null beta}) → dynamic/Null {}
-  method namedCallback(({alpha: dynamic, beta: dynamic}) → dynamic/Nothing callback) → dynamic/Null {}
+  method namedCallback(({alpha: core::String, beta: core::int}) → dynamic/Nothing callback) → dynamic/Null {}
 }
 static method topLevelNamed(dynamic/core::int* {int} beta, dynamic/core::int* {int} alpha, {dynamic/core::int* {null,int} delta, dynamic/core::int* {null,int} gamma}) → dynamic/Null {}
 static method topLevelOptional(dynamic/Nothing beta, dynamic/Nothing alpha, [dynamic/Null gamma, dynamic/Null delta]) → dynamic/Null {}