get_file_argument() is responsible to extract the relative path
of the file to be served by a specific Moodle component
like a theme or a module.
Some modules like scorm and imscp require slasharguments support
and they force it when creating the URLs to serve their files.
It should honor the slasharguments setting but this could break
those instances where existing hard-coded links still make usage of
the "old" format, the one when slasharguments is set to No i.e. '?file='.
Its logic has been improved by looking at when the URL is related to
serving a plug-in file in a "forced" slasharguments way of serving it
i.e. using '/pluginfile.php/' and not '/pluginfile.php?'.
Matteo Scaramuccia
ea76a7cde3