Since these are just interpreted comments, there's 0 impact on actual code.
This removes all lines that match /* vim: set(.*)tw=80: */ with S&R -- there are
a few others scattered around which will be removed manually in a second part.
This is a B2G leftover, was proprietary, and is causing issues
because `AudioContext` can now have a parameter that is a property bag,
per spec (we do not do anything with the property bag now; the audio
back-end will use automatic values for everything).
This resolves#924.
