Be more careful about converting between file URIs and paths.

This happened to work on Windows because it interprets forward slashes as
directory separators.

Review URL: https://codereview.chromium.org//13191011

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart/pkg/stack_trace@20708 260f80e4-7a28-3924-810f-c04153c831b5
3 files changed
tree: d2cf3b8a234174b6803857d5f2f0506322d8d211
  1. pkgs/