Revert "Library functions can never be constructors."

sdk/lib/_internal/compiler/implementation/resolution/members.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of resolution;
 
 abstract class TreeElements {
   Element get currentElement;
   Setlet<Node> get superUses;
 
@@ skipping 437 matching lines @@
         // Hack: Use unparser to test parameter equality. This only works
         // because we are restricting patch uses and the approach cannot be used
         // elsewhere.
 
         // The node contains the type, so there is a potential overlap.
         // Therefore we only check the text if the types are identical.
         String originParameterText =
             originParameter.parseNode(compiler).toString();
         String patchParameterText =
             patchParameter.parseNode(compiler).toString();
-        if (originParameterText != patchParameterText) {
+        if (originParameterText != patchParameterText
+            // We special case the list constructor because of the
+            // optional parameter.
+            && origin != compiler.unnamedListConstructor) {
           compiler.reportError(
               originParameter.parseNode(compiler),
               MessageKind.PATCH_PARAMETER_MISMATCH,
               {'methodName': origin.name,
                'originParameter': originParameterText,
                'patchParameter': patchParameterText});
           compiler.reportInfo(patchParameter,
               MessageKind.PATCH_POINT_TO_PARAMETER,
               {'parameterName': patchParameter.name});
         }
@@ skipping 4361 matching lines @@
 }
 
 /// The result for the resolution of the `assert` method.
 class AssertResult implements ResolutionResult {
   const AssertResult();
 
   Element get element => null;
 
   String toString() => 'AssertResult()';
 }