[gnome-shell] dateMenu: Don't generate JS garbage every clock tick

[Jasper St. Pierre <jstpierre src gnome org>]

commit 42066a7c4674cab9ce0da0ed29b463ea9271a636
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Wed Oct 1 15:28:14 2014 -0600

    dateMenu: Don't generate JS garbage every clock tick
    
    Instead of waking up the JS every second to set the clock and update a
    date label the user will rarely see, simply use property binding to
    bypass JS string handling, and update the date in the menu when the menu
    is opened.

 js/ui/dateMenu.js |   20 ++++++++------------
 1 files changed, 8 insertions(+), 12 deletions(-)
---
diff --git a/js/ui/dateMenu.js b/js/ui/dateMenu.js
index 1a86a6a..db8f2a5 100644
--- a/js/ui/dateMenu.js
+++ b/js/ui/dateMenu.js
@@ -3,6 +3,7 @@
 const GLib = imports.gi.GLib;
 const Gio = imports.gi.Gio;
 const GnomeDesktop = imports.gi.GnomeDesktop;
+const GObject = imports.gi.GObject;
 const Lang = imports.lang;
 const Mainloop = imports.mainloop;
 const Cairo = imports.cairo;
@@ -124,14 +125,19 @@ const DateMenuButton = new Lang.Class({
             if (isOpen) {
                 let now = new Date();
                 this._calendar.setDate(now);
+
+                /* Translators: This is the date format to use when the calendar popup is
+                 * shown - it is shown just below the time in the shell (e.g. "Tue 9:29 AM").
+                 */
+                let dateFormat = _("%A %B %e, %Y");
+                this._date.set_label(now.toLocaleFormat(dateFormat));
             }
         }));
 
         // Done with hbox for calendar and event list
 
         this._clock = new GnomeDesktop.WallClock();
-        this._clock.connect('notify::clock', Lang.bind(this, this._updateClockAndDate));
-        this._updateClockAndDate();
+        this._clock.bind_property('clock', this._clockDisplay, 'text', GObject.BindingFlags.SYNC_CREATE);
 
         Main.sessionMode.connect('updated', Lang.bind(this, this._sessionUpdated));
         this._sessionUpdated();
@@ -196,16 +202,6 @@ const DateMenuButton = new Lang.Class({
         this._dateAndTimeSeparator.actor.visible = Main.sessionMode.allowSettings;
     },
 
-    _updateClockAndDate: function() {
-        this._clockDisplay.set_text(this._clock.clock);
-        /* Translators: This is the date format to use when the calendar popup is
-         * shown - it is shown just below the time in the shell (e.g. "Tue 9:29 AM").
-         */
-        let dateFormat = _("%A %B %e, %Y");
-        let displayDate = new Date();
-        this._date.set_label(displayDate.toLocaleFormat(dateFormat));
-    },
-
     _getCalendarApp: function() {
         if (this._calendarApp !== undefined)
             return this._calendarApp;