dart2dart: fix top level field declarations.

lib/compiler/implementation/dart_backend/backend.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.
 
 class BailoutException {
   final String reason;
 
   const BailoutException(this.reason);
 }
 
@@ skipping 30 matching lines @@
     void bailout(String reason) {
       throw new BailoutException(reason);
     }
 
     try {
       StringBuffer sb = new StringBuffer();
       resolvedElements.forEach((element, treeElements) {
         if (!element.isTopLevel()) {
           bailout('Cannot process non top-level $element');
         }
-        sb.add(element.parseNode(compiler).unparse());
+
+        if (element.isField()) {
+          // Add modifiers first.
+          sb.add(element.modifiers.toString());
+          sb.add(' ');
+          // Figure out type.
+          if (element is VariableElement) {
+            VariableListElement variables = element.variables;
+            if (variables.type !== null) {
+              sb.add(variables.type);
+              sb.add(' ');
+            }
+          }
+          // TODO(smok): Maybe not rely on node unparsing,
+          // but unparse initializer manually.
+          sb.add(element.parseNode(compiler).unparse());
+          sb.add(';');
+        } else {
+          sb.add(element.parseNode(compiler).unparse());
+        }
       });
       compiler.assembledCode = sb.toString();
     } catch (BailoutException e) {
       compiler.assembledCode = '''
 main() {
   final bailout_reason = "${e.reason}";
 }
 ''';
     }
   }
 
   log(String message) => compiler.log('[DartBackend] $message');
 }