Bug 991981 - ArrayBufferInputStream test.  r=sfink, r=jdm

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extra : rebase_source : b50ffa49289aeb42bd4550b846934865b9c6f8d7
Add ecma_6/extensions/{shell,browser}.js so that tests work in shells other than mine.  Followup to a bunch of bugs, no bug for the general issue, r=oops

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extra : rebase_source : 04ef57df1b0ad649b94021ba910de99531b3d0db