[mutter] backend: Make the getter use the cached ui scale

[Jonas Ådahl <jadahl src gnome org>]

commit 43cdf81f6b942d129be465a409f23708c8c360bb
Author: Jonas Ådahl <jadahl gmail com>
Date:   Mon Apr 10 17:33:45 2017 +0800

    backend: Make the getter use the cached ui scale
    
    The cached ui scale is kept up to date, so don't recalculate it
    everytime meta_backend_get_ui_scaling() is called.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=777732

 src/backends/meta-backend.c |   17 ++++++++++++++---
 1 files changed, 14 insertions(+), 3 deletions(-)
---
diff --git a/src/backends/meta-backend.c b/src/backends/meta-backend.c
index 9d1d310..5741207 100644
--- a/src/backends/meta-backend.c
+++ b/src/backends/meta-backend.c
@@ -114,6 +114,9 @@ G_DEFINE_ABSTRACT_TYPE_WITH_CODE (MetaBackend, meta_backend, G_TYPE_OBJECT,
                                   G_IMPLEMENT_INTERFACE (G_TYPE_INITABLE,
                                                          initable_iface_init));
 
+static int
+meta_backend_calculate_ui_scaling_factor (MetaBackend *backend);
+
 static void
 meta_backend_finalize (GObject *object)
 {
@@ -163,7 +166,7 @@ meta_backend_update_ui_scaling_factor (MetaBackend *backend)
   MetaBackendPrivate *priv = meta_backend_get_instance_private (backend);
   int ui_scaling_factor;
 
-  ui_scaling_factor = meta_backend_get_ui_scaling_factor (backend);
+  ui_scaling_factor = meta_backend_calculate_ui_scaling_factor (backend);
 
   if (ui_scaling_factor != priv->ui_scaling_factor)
     {
@@ -1156,8 +1159,8 @@ calculate_ui_scaling_factor (MetaBackend *backend)
   return max_scale;
 }
 
-int
-meta_backend_get_ui_scaling_factor (MetaBackend *backend)
+static int
+meta_backend_calculate_ui_scaling_factor (MetaBackend *backend)
 {
   if (meta_is_stage_views_scaled ())
     {
@@ -1172,6 +1175,14 @@ meta_backend_get_ui_scaling_factor (MetaBackend *backend)
     }
 }
 
+int
+meta_backend_get_ui_scaling_factor (MetaBackend *backend)
+{
+  MetaBackendPrivate *priv = meta_backend_get_instance_private (backend);
+
+  return priv->ui_scaling_factor;
+}
+
 void
 meta_backend_notify_ui_scaling_factor_changed (MetaBackend *backend)
 {