Made dart2js constructor lookup logic "private"-aware, fixed 4740 bug.

lib/compiler/implementation/universe/universe.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.
 
 #library('universe');
 
 #import('../closure.dart');
 #import('../elements/elements.dart');
 #import('../leg.dart');
 #import('../scanner/scannerlib.dart');
@@ skipping 168 matching lines @@
       : this(SelectorKind.CALL, name, library, arity, named);
 
   Selector.callClosure(int arity, [List<SourceString> named = const []])
       : this(SelectorKind.CALL, Compiler.CALL_OPERATOR_NAME, null,
              arity, named);
 
   Selector.callClosureFrom(Selector selector)
       : this(SelectorKind.CALL, Compiler.CALL_OPERATOR_NAME, null,
              selector.argumentCount, selector.namedArguments);
 
+  Selector.callConstructor(SourceString constructorName,
+                           LibraryElement library)
+      : this(SelectorKind.CALL,
+             constructorName,
+             library,
+             0,
+             const []);
+
+  Selector.callDefaultConstructor(LibraryElement library)
+      : this(SelectorKind.CALL, const SourceString(""), library, 0, const []);
+
   // TODO(kasperl): This belongs somewhere else.
   Selector.noSuchMethod()
       : this(SelectorKind.CALL, Compiler.NO_SUCH_METHOD, null, 2);
 
   bool isGetter() => kind === SelectorKind.GETTER;
   bool isSetter() => kind === SelectorKind.SETTER;
   bool isCall() => kind === SelectorKind.CALL;
 
   bool isIndex() => kind === SelectorKind.INDEX && argumentCount == 1;
   bool isIndexSet() => kind === SelectorKind.INDEX && argumentCount == 2;
@@ skipping 325 matching lines @@
 
     if (!self.isInterface() && self.isSubclassOf(other)) {
       // Resolve an invocation of [element.name] on [self]. If it
       // is found, this selector is a candidate.
       return hasElementIn(self, element) && appliesUntyped(element, compiler);
     }
 
     return false;
   }
 }