Bug 969768: Fix "Reload application" button on the Gaia browser-helper extension

I know atleast two other people had this problem on OSX + Firefox Nightly (Feb 7) + gaia @ f8dd1f477f2362abed76aec31ff29f1c5e87ec3d. I'm not sure how wide-spread this problem is. But this fixes it atleast for us three and makes app development oh-so-much-nicer <3

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