Bug 1071858 - aria-hidden elements will not be part of childCount when traversing. r=eeejay

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 accessible/jsat/TraversalRules.jsm                 |  4 ++--
 accessible/jsat/Utils.jsm                          | 10 +++++++++
 accessible/tests/mochitest/jsat/doc_traversal.html | 24 ++++++++++++++++++++++
 .../tests/mochitest/jsat/test_traversal.html       | 18 ++++++++--------
 4 files changed, 46 insertions(+), 10 deletions(-)