Bug 1054454 - added support for aria-hidden attribute changes. Added output filter wh when presenting aria-hidden elements. r=eeejay

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 accessible/jsat/AccessFu.jsm                       |   4 +
 accessible/jsat/EventManager.jsm                   |  92 ++++++++++-----
 accessible/jsat/Utils.jsm                          |  14 ++-
 .../mochitest/jsat/doc_content_integration.html    |  17 +++
 .../mochitest/jsat/test_content_integration.html   |  67 +++++++++++
 .../tests/mochitest/jsat/test_live_regions.html    | 129 ++++++++++++++++++++-
 6 files changed, 287 insertions(+), 36 deletions(-)