Purge String operator+ from dart2js.

dart/utils/compiler/build_helper.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.
 
 #import('dart:io');
 #import('dart:uri');
 
 #import('../../lib/compiler/implementation/util/uri_extras.dart');
 #import('../../lib/compiler/implementation/filenames.dart');
 
@@ skipping 55 matching lines @@
   Uri dart2jsUri = dartUri.resolve('lib/compiler/implementation/dart2js.dart');
   String dart2jsPath = relativize(dartVmLocation, dart2jsUri);
   String dart2jsPathWin = dart2jsPath.replaceAll("/", "\\");
 
   print('dartUri = $dartUri');
   print('dartVmLocation = $dartVmLocation');
   print('dart2jsUri = $dart2jsUri');
   print('dart2jsPath = $dart2jsPath');
   print('dart2jsPathWin = $dart2jsPathWin');
 
+  // Disable String operator+. This should only be necessary
+  // temporarily as the operator will go away soon.
+  // TODO(ahe): Remove this option.
+  options = ' --allow_string_plus=false$options';
+
   return [
 '''
 #!/bin/sh
 # 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.
 
 BIN_DIR=`dirname \$0`
 exec \$BIN_DIR/dart$options \$BIN_DIR/$dart2jsPath "\$@"
 ''',
 '''
 @echo off
 REM Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 REM for details. All rights reserved. Use of this source code is governed by a
 REM BSD-style license that can be found in the LICENSE file.
 
 set SCRIPTPATH=%~dp0
 
 REM Does the path have a trailing slash? If so, remove it.
 if %SCRIPTPATH:~-1%==\ set SCRIPTPATH=%SCRIPTPATH:~0,-1%
 
 set arguments=%*
 
 "%SCRIPTPATH%\dart.exe"$options "%SCRIPTPATH%$dart2jsPathWin" %arguments%
 '''.replaceAll('\n', '\r\n')];
 }