[mutter] prefs: Update cursor size based on xsettings

[Adel Gadllah <agadllah src gnome org>]

commit 493c0f71d2084210e8420d26f12dfb4439376d8f
Author: Adel Gadllah <adel gadllah gmail com>
Date:   Mon Jul 28 11:02:03 2014 +0200

    prefs: Update cursor size based on xsettings
    
    We shouldn't scale the cursor size in mutter we g-s-d exports
    the correct size on hidpi so use gtk-cursor-theme-size.
    
    This way we also catch changes on resolution updates.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=729337

 src/core/prefs.c |   32 ++++++++++++++++++++++++++++++++
 1 files changed, 32 insertions(+), 0 deletions(-)
---
diff --git a/src/core/prefs.c b/src/core/prefs.c
index ed73e5d..336bc33 100644
--- a/src/core/prefs.c
+++ b/src/core/prefs.c
@@ -137,6 +137,10 @@ static void xsettings_overrides_changed (GSettings  *settings,
                                          gchar      *key,
                                          gpointer    data);
 
+static void update_cursor_size (GtkSettings *settings,
+                                GParamSpec *pspec,
+                                gpointer data);
+
 static void queue_changed (MetaPreference  pref);
 
 static void maybe_give_disable_workarounds_warning (void);
@@ -1012,6 +1016,9 @@ meta_prefs_init (void)
       xsettings_overrides_changed (settings, KEY_XSETTINGS_OVERRIDES, NULL);
     }
 
+  g_signal_connect (gtk_settings_get_default (), "notify::gtk-cursor-theme-size",
+                    G_CALLBACK (update_cursor_size), NULL);
+
   settings = g_settings_new (SCHEMA_INPUT_SOURCES);
   g_signal_connect (settings, "changed::" KEY_XKB_OPTIONS,
                     G_CALLBACK (settings_changed), NULL);
@@ -1032,6 +1039,8 @@ meta_prefs_init (void)
   handle_preference_init_string_array ();
   handle_preference_init_int ();
 
+  update_cursor_size (gtk_settings_get_default (), NULL, NULL);
+
   init_bindings ();
 }
 
@@ -1270,6 +1279,29 @@ out:
     queue_changed (META_PREF_BUTTON_LAYOUT);
 }
 
+static void
+update_cursor_size (GtkSettings *settings,
+                    GParamSpec *pspec,
+                    gpointer data)
+{
+  GdkScreen *screen = gdk_screen_get_default ();
+  GValue value = G_VALUE_INIT;
+  int xsettings_cursor_size = 24;
+
+  g_value_init (&value, G_TYPE_INT);
+  if (gdk_screen_get_setting (screen, "gtk-cursor-theme-size", &value))
+    {
+      xsettings_cursor_size = g_value_get_int (&value);
+    }
+
+  if (xsettings_cursor_size != cursor_size)
+    {
+      cursor_size = xsettings_cursor_size;
+      queue_changed (META_PREF_CURSOR_SIZE);
+    }
+}
+
+
 /**
  * maybe_give_disable_workaround_warning:
  *