Remove the `this.actor = ...` and `this.actor._delegate = this` patterns in most
of classes, by inheriting all the actor container classes.
Uses interfaces when needed for making sure that multiple classes will implement
some required methods or to avoid redefining the same code multiple times.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/559
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
Miscellaneous fixes from review:
- Distribute calendar.js and the interactive test
- Make the pointless protection against leap seconds actually work
by starting in the middle of the day so that forward/back always
move a day.
- Use a variable instead of an inline '8' to know where to start
when removing old day actors.
- Remove a stray comment from the test
https://bugzilla.gnome.org/show_bug.cgi?id=596432
js/ui/calendar.js: Generic calendar widget
tests/interactive/calendar.js: Basic test of the calendar
js/ui/panel.js: Add a pop-down from the clock that shows a
calendar widget. The pop-down is not menu-like to allow the user to
interact with an application while looking at the calendar.
gnome-shell.css: Add theming for calendar, calendar popup, and for
buttons on the panel
https://bugzilla.gnome.org/show_bug.cgi?id=596432
