color-manager: Set up a D-Bus proxy to org.gnome.SettingsDaemon.Color

gsd-color provides this API, which exposes details about the night light
state. Currently, gsd-color also turns this state into CRTC gamma
changes, but this will eventually change, and this is a preparation for
this.

The proxy isn't yet used for anything.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2164>

src/tests/dbusmock-templates/gsd-color.py

@@ -0,0 +1,31 @@
+'''gsd-color proxy mock template
+'''
+
+# This program is free software; you can redistribute it and/or modify it under
+# the terms of the GNU Lesser General Public License as published by the Free
+# Software Foundation; either version 3 of the License, or (at your option) any
+# later version.  See http://www.gnu.org/copyleft/lgpl.html for the full text
+# of the license.
+
+__author__ = 'Jonas Ådahl'
+__copyright__ = '(c) 2021 Red Hat Inc.'
+
+import dbus
+import os
+from dbusmock import MOCK_IFACE
+
+
+BUS_NAME = 'org.gnome.SettingsDaemon.Color'
+MAIN_OBJ = '/org/gnome/SettingsDaemon/Color'
+MAIN_IFACE = BUS_NAME
+SYSTEM_BUS = False
+
+
+def load(mock, parameters=None):
+    mock.night_light_active = False
+    mock.temperature = 6500
+
+    mock.AddProperty(MAIN_IFACE, 'NightLightActive', dbus.Boolean())
+    mock.AddProperty(MAIN_IFACE, 'Temperature', dbus.UInt32())
+    mock.Set(MAIN_IFACE, 'NightLightActive', mock.night_light_active)
+    mock.Set(MAIN_IFACE, 'Temperature', dbus.UInt32(mock.temperature))

src/tests/meta-dbus-runner.py

@@ -43,6 +43,7 @@ class MutterDBusTestCase(DBusTestCase):
 
         klass.start_from_local_template('localed')
         klass.start_from_local_template('colord')
+        klass.start_from_local_template('gsd-color')
 
         klass.system_bus_con = klass.get_dbus(system_bus=True)
         klass.session_bus_con = klass.get_dbus(system_bus=False)