bug 875760 spdy/3 credential nop implementation r=hurley

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extra : rebase_source : 44d41e9efa69f650e315ce9308f93273445f0921
bug 875093 - spdy flow control window calculation > 31bits r=hurley

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extra : rebase_source : ef84817a329ab86e1320eaac64b67a2859f0370f
bug 874170 - default npn protocol should be http/1.1 r=hurley

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extra : rebase_source : 3c772fd36262f9a7bacbfc5d4d3cfe15d700973d