Bug 851378 - Move removing the plugin prototype from objects to content. r=bsmedberg a=bbajaj
Bug 851378 - Notify owning content when we destroy plugins from under it. r=bsmedberg a=bbajaj
Bug 851378 - Avoid bogus assertion when trying to spawn disabled plugin. r=bsmedberg a=bbajaj
Bug 843671 - Fix plugin instance owner teardown. r=bsmedberg a=bbajaj