Enable coverage tool to handle multiple files and libraries
Enable coverage tool to handle multiple files and libraries

Coverage tool now enables stepping for all libraries with a
url other than "dart:" and "package:"

R=srdjan@google.com

Review URL: https://codereview.chromium.org//19772004

git-svn-id: c93d8a2297af3b929165606efe145742a534bc71@25167 260f80e4-7a28-3924-810f-c04153c831b5

dart-archive/dart-sdk,dartino/dart-sdk,dartino/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-lang/sdk,dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dartino/dart-sdk,dart-lang/sdk,dartino/dart-sdk