dart:io: Use PathBuffer class for Directory.list on Windows platform.

dart:io: Use PathBuffer class for Directory.list on Windows platform.


BUG=https://code.google.com/p/dart/issues/detail?id=7505

Committed: https://code.google.com/p/dart/source/detail?r=18448

[Bill Hesse, 2013-02-13 14:41:40]

https://codereview.chromium.org/12252006/diff/1/runtime/bin/directory_win.cc
File runtime/bin/directory_win.cc (right):

https://codereview.chromium.org/12252006/diff/1/runtime/bin/directory_win.cc#...
runtime/bin/directory_win.cc:69: return ok && (!recursive ||
ListRecursively(path->data, recursive, listing));
Line 69 is the only change from the previously committed version of this change.
 The previous version fell off the end and returned null if recursive was false,
because the return true from the current code was removed.

[Florian Schneider, 2013-02-13 14:58:33]

lgtm