Bug 945222 - Use queues for IPC rather than Pipes, which seems to help on OSX.

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extra : rebase_source : 61b4f0f071305d4ee258935155345336b41c351d
Bug 945222 - Update web-platform-tests to revision c7f8c512845a6254db88de322bd96920f0a285f1

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extra : rebase_source : e3baf2d7d0548f281a001adab6a58f06a59128ea