Roll Observatory packages and add a roll script

packages/dart_style/lib/src/debug.dart

 // Copyright (c) 2014, 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.
 
 /// Internal debugging utilities.
 library dart_style.src.debug;
 
 import 'dart:math' as math;
 
 import 'chunk.dart';
@@ skipping 196 matching lines @@
 
       if (chunk.spaceWhenUnsplit) buffer.write(" ");
     }
   }
 
   buffer.write(chunks.last.text);
   log(buffer);
 }
 
 String _color(String ansiEscape) => useAnsiColors ? ansiEscape : "";