Handle unresolved elements in the new IR

sdk/lib/_internal/compiler/implementation/ir/ir_nodes.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.
 
 // IrNodes are kept in a separate library to have precise control over their
 // dependencies on other parts of the system.
 library dart2js.ir_nodes;
 
 import '../dart2jslib.dart' as dart2js show Constant, ConstructedConstant,
   StringConstant, ListConstant, MapConstant;
@@ skipping 187 matching lines @@
            (selector.kind == SelectorKind.INDEX && arguments.length == 1) ||
            (selector.kind == SelectorKind.INDEX && arguments.length == 2));
   }
 
   accept(Visitor visitor) => visitor.visitInvokeSuperMethod(this);
 }
 
 /// Non-const call to a constructor. The [target] may be a generative
 /// constructor, factory, or redirecting factory.
 class InvokeConstructor extends Expression implements Invoke {
-  final GenericType type;
+  final DartType type;
   final FunctionElement target;
   final Reference continuation;
   final List<Reference> arguments;
   final Selector selector;
 
   /// The class being instantiated. This is the same as `target.enclosingClass`
   /// and `type.element`.
   ClassElement get targetClass => target.enclosingElement;
 
   /// True if this is an invocation of a factory constructor.
   bool get isFactory => target.isFactoryConstructor;
 
   InvokeConstructor(this.type,
                     this.target,
                     this.selector,
                     Continuation cont,
                     List<Definition> args)
       : continuation = new Reference(cont),
         arguments = _referenceList(args) {
-    assert(target.isConstructor);
-    assert(type.element == target.enclosingElement);
+    assert(target.isErroneous || target.isConstructor);
+    assert((target.isErroneous && type.isDynamic) ||
+        type.element == target.enclosingElement);
   }
 
   accept(Visitor visitor) => visitor.visitInvokeConstructor(this);
 }
 
 class AsCast extends Expression {
   final Reference receiver;
   final DartType type;
   final Reference continuation;
 
@@ skipping 487 matching lines @@
     for (int i = node.parameters.length - 1; i >= 0; --i) {
       release(node.parameters[i]);
     }
   }
 
   void visitIsTrue(IsTrue node) {
     visitReference(node.value);
   }
 
 }