Removes the init() function in favor of executing all environment
changes when the file is imported.
Additionally ports all unit tests using imports.gi.environment.init() to
use the updated module.
Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2822>
The author of the original URL-matching regex warns[0] that the pattern may
cause certain regex engines to lock up with certain input, namely patterns
that contain parentheses. It turns out SpiderMonkey is affected, but rather
than switching to the author's improved version (that is still crazy), sim-
plify the pattern a bit by removing support for nested parentheses in URLs.
Even a single pair of parentheses is extremely rare, so this is unlikely to
make a noticeable difference (other than not locking up SpiderMonkey of
course) ...
[0] http://daringfireball.net/2010/07/improved_regex_for_matching_urls
js2-mode is no longer developed and we recommend js-mode these days,
so switch the modelines to specify that, and make them consistent
across all files.
https://bugzilla.gnome.org/show_bug.cgi?id=660358
