Fix source spans hashcode implementation

R=justinfagnani@google.com

Review URL: https://codereview.chromium.org//20600002

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart/pkg/source_maps@25514 260f80e4-7a28-3924-810f-c04153c831b5
2 files changed
tree: 2944cb71925004d09a6dce8da24477e6c6918bb6
  1. pkgs/