Do not duplicate constructors for named mixin applications.

testcases/type-propagation/redirecting_factory.baseline.txt

Index: testcases/type-propagation/redirecting_factory.baseline.txt
diff --git a/testcases/type-propagation/redirecting_factory.baseline.txt b/testcases/type-propagation/redirecting_factory.baseline.txt
index 302f551e380d8aa5287ca7fb57ca373b49738cc8..20a2d4c80835149799f991fd7c5bbf0de1dfb2d7 100644
--- a/testcases/type-propagation/redirecting_factory.baseline.txt
+++ b/testcases/type-propagation/redirecting_factory.baseline.txt
@@ -45,9 +45,6 @@ class Mix<M extends core::Object> extends self::Base<self::Mix::M> implements se
   constructor •() → void
     : super self::Base::•()
     ;
-  constructor •() → void
-    : super self::Base::•()
-    ;
 }
 static method main() → dynamic/Null {
   core::print(new self::Bar::•<core::String, core::double>(4).x);