Make the dart:developer library available in DDC so debugger statement works

pkg/dev_compiler/tool/build_sdk.dart

 #!/usr/bin/env dart
 // Copyright (c) 2016, 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.
 
 /// A straightforward script that builds the SDK.
 ///
 /// This would be easy enough to do in a shell script, as we go through the
 /// command line interface. But being able to build from a Dart library means
 /// we can call this during code coverage to get more realistic numbers.
@@ skipping 17 matching lines @@
     'dart:_js_embedded_names',
     'dart:_js_helper',
     'dart:_js_mirrors',
     'dart:_js_primitives',
     'dart:_metadata',
     'dart:_native_typed_data',
     'dart:async',
     'dart:collection',
     'dart:convert',
     'dart:core',
+    'dart:developer',
     'dart:isolate',
     'dart:js',
     'dart:js_util',
     'dart:math',
     'dart:mirrors',
     'dart:typed_data',
     'dart:indexed_db',
     'dart:html',
     'dart:html_common',
     'dart:svg',
     'dart:web_audio',
     'dart:web_gl',
     'dart:web_sql'
   ]);
   compile(args);
 }