style: Disable camelcase rule for GObject properties

For GObject properties, we follow the convention of all-lowercase,
dash-separated names. Those translate to underscores in getters/setters,
so exempt them from the newly added "camelcase" rule.

https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/627

js/perf/hwtest.js

@@ -6,6 +6,7 @@
             script_redrawTestDone, script_collectTimings,
             script_geditLaunch, script_geditFirstFrame,
             clutter_stagePaintStart, clutter_paintCompletedTimestamp */
+/* eslint camelcase: ["error", { properties: "never", allow: ["^script_", "^clutter"] }] */
 const { Clutter, Gio, Shell } = imports.gi;
 const Main = imports.ui.main;
 const Scripting = imports.ui.scripting;