Support default constructors in analyzer2dart.

pkg/compiler/lib/src/cps_ir/cps_ir_builder_visitor.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.
 
 part of dart2js.ir_builder;
 
 /**
  * This task iterates through all resolved elements and builds [ir.Node]s. The
  * nodes are stored in the [nodes] map and accessible through [hasIr] and
  * [getIr].
@@ skipping 49 matching lines @@
       });
     });
   }
 
   bool canBuild(Element element) {
     if (element is TypedefElement) return false;
     if (element is FunctionElement) {
       // TODO(sigurdm): Support native functions for dart2js.
       assert(invariant(element, !element.isNative));
 
-      // TODO(kmillikin,sigurdm): Support constructors.
-      if (element is ConstructorElement && !element.isGenerativeConstructor) {
-        return false;
+      if (element is ConstructorElement) {
+        if (!element.isGenerativeConstructor) {
+          // TODO(kmillikin,sigurdm): Support constructors.
+          return false;
+        }
+        if (element.isSynthesized) {
+          // Do generate CPS for synthetic constructors.
+          return true;
+        }
       }
-
     } else if (element is! FieldElement) {
       compiler.internalError(element, "Unexpected element type $element");
     }
     return compiler.backend.shouldOutput(element);
   }
 
   bool get inCheckedMode {
     bool result = false;
     assert((result = true));
     return result;
@@ skipping 1455 matching lines @@
         element,
         node,
         elements);
     IrBuilder builder =
         new JsIrBuilder(compiler.backend.constantSystem, element);
     return withBuilder(builder, () => _makeFunctionBody(element, node));
   }
 
 }