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 splits ScriptLoader up the same way Mozilla did with the exception of
ScriptRequest due to the fact that ScriptLoader and ScriptRequest are
interdependent and would create a circular dependency if split apart when not
using unified building.