dart2js: set effective target for patched constructors

pkg/compiler/lib/src/elements/modelx.dart

 // Copyright (c) 2013, 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.
 
 library elements.modelx;
 
 import '../common/resolution.dart' show
     Resolution,
     Parsing;
 import '../compiler.dart' show
@@ skipping 2185 matching lines @@
   void set effectiveTarget(ConstructorElement constructor) {
     assert(constructor != null && internalEffectiveTarget == null);
     internalEffectiveTarget = constructor;
   }
 
   ConstructorElement get effectiveTarget {
     if (Elements.isErroneous(immediateRedirectionTarget)) {
       return immediateRedirectionTarget;
     }
     assert(!isRedirectingFactory || internalEffectiveTarget != null);
-    return isRedirectingFactory ? internalEffectiveTarget : this;
+    if (isRedirectingFactory) return internalEffectiveTarget;
+    if (isPatched) {

[Johnni Winther, 2015/10/06 10:38:14]

Why is this needed?

[Harry Terkelsen, 2015/10/12 18:17:44]

There are targets that are patched but are not redirecting factories, so we need
to check that internalEffectiveTarget is set (by the method which resolves
chains of redirecting factories)

+      return internalEffectiveTarget ?? this;
+    }
+    return this;
   }
 
   InterfaceType computeEffectiveTargetType(InterfaceType newType) {
     if (!isRedirectingFactory) return newType;
     assert(invariant(this, effectiveTargetType != null,
         message: 'Redirection target type has not yet been computed for '
                  '$this.'));
     return effectiveTargetType.substByContext(newType);
   }
 
@@ skipping 886 matching lines @@
   AstElement get definingElement;
 
   bool get hasResolvedAst => definingElement.hasTreeElements;
 
   ResolvedAst get resolvedAst {
     return new ResolvedAst(declaration,
         definingElement.node, definingElement.treeElements);
   }
 
 }