[gtk+] headerbar: simplify some size allocation code

[Ray Strode <halfline src gnome org>]

commit eccfce50d6835206f7260937579bf363bdec1477
Author: Ray Strode <rstrode redhat com>
Date:   Fri Jun 24 07:57:06 2016 -0400

    headerbar: simplify some size allocation code
    
    With a headerbar, the widget in the center may be a label, constructed
    internally, or a custom widget, constructed externally.  The size
    allocation code needs to handle either case the same way for the most
    part.  There's more than one place in the code that checks which of
    the two widgets to use and does some operation on the selected one.
    
    This commit simplifies the code by checking up front which one is the
    center (title) widget and storing that in a temporary variable,
    This allows reducing duplicated logic later on in the function.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=724332

 gtk/gtkheaderbar.c |   32 ++++++++++++++------------------
 1 files changed, 14 insertions(+), 18 deletions(-)
---
diff --git a/gtk/gtkheaderbar.c b/gtk/gtkheaderbar.c
index c16cf8a..eba695b 100644
--- a/gtk/gtkheaderbar.c
+++ b/gtk/gtkheaderbar.c
@@ -989,6 +989,7 @@ gtk_header_bar_allocate_contents (GtkCssGadget        *gadget,
                                   gpointer             unused)
 {
   GtkWidget *widget = gtk_css_gadget_get_owner (gadget);
+  GtkWidget *title_widget;
   GtkHeaderBar *bar = GTK_HEADER_BAR (widget);
   GtkHeaderBarPrivate *priv = gtk_header_bar_get_instance_private (bar);
   GtkRequestedSize *sizes;
@@ -1034,21 +1035,19 @@ gtk_header_bar_allocate_contents (GtkCssGadget        *gadget,
   title_minimum_size = 0;
   title_natural_size = 0;
 
-  if (priv->custom_title &&
+  if (priv->custom_title != NULL &&
       gtk_widget_get_visible (priv->custom_title))
-    {
-      gtk_widget_get_preferred_width_for_height (priv->custom_title,
-                                                 height,
-                                                 &title_minimum_size,
-                                                 &title_natural_size);
-    }
+    title_widget = priv->custom_title;
   else if (priv->label_box != NULL)
-    {
-      gtk_widget_get_preferred_width_for_height (priv->label_box,
-                                                 height,
-                                                 &title_minimum_size,
-                                                 &title_natural_size);
-    }
+    title_widget = priv->label_box;
+  else
+    title_widget = NULL;
+
+  if (title_widget)
+    gtk_widget_get_preferred_width_for_height (title_widget,
+                                               height,
+                                               &title_minimum_size,
+                                               &title_natural_size);
   width -= title_natural_size;
 
   start_width = 0;
@@ -1146,11 +1145,8 @@ gtk_header_bar_allocate_contents (GtkCssGadget        *gadget,
   if (direction == GTK_TEXT_DIR_RTL)
     child_allocation.x = allocation->x + allocation->width - (child_allocation.x - allocation->x) - 
child_allocation.width;
 
-  if (priv->custom_title != NULL &&
-      gtk_widget_get_visible (priv->custom_title))
-    gtk_widget_size_allocate (priv->custom_title, &child_allocation);
-  else if (priv->label_box != NULL)
-    gtk_widget_size_allocate (priv->label_box, &child_allocation);
+  if (title_widget != NULL)
+    gtk_widget_size_allocate (title_widget, &child_allocation);
 
   child_allocation.y = allocation->y;
   child_allocation.height = height;