[gtk+] toolbutton: Fix off-center icons

[Matthias Clasen <matthiasc src gnome org>]

commit 5ce2d77691743945ac63f6f63f98156dc7b8972b
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Jan 7 12:42:27 2018 -0500

    toolbutton: Fix off-center icons
    
    When the toolbar style is both-horiz, and the item
    is not important, we were not centering the icon in the
    same way as in gtk3. The reason is that we overlooked
    the expand child property being set to TRUE in this case.

 gtk/gtktoolbutton.c |   12 ++++++++++--
 1 files changed, 10 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtktoolbutton.c b/gtk/gtktoolbutton.c
index 4286a8e..5f25715 100644
--- a/gtk/gtktoolbutton.c
+++ b/gtk/gtktoolbutton.c
@@ -514,7 +514,11 @@ gtk_tool_button_construct_contents (GtkToolItem *tool_item)
        {
           box = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0);
          if (icon)
-            gtk_box_pack_start (GTK_BOX (box), icon);
+            {
+              gtk_box_pack_start (GTK_BOX (box), icon);
+              if (!label)
+                gtk_widget_set_hexpand (icon, TRUE);
+            }
          if (label)
             gtk_box_pack_end (GTK_BOX (box), label);
        }
@@ -522,7 +526,11 @@ gtk_tool_button_construct_contents (GtkToolItem *tool_item)
        {
           box = gtk_box_new (GTK_ORIENTATION_VERTICAL, 0);
          if (icon)
-            gtk_box_pack_end (GTK_BOX (box), icon);
+            {
+              gtk_box_pack_end (GTK_BOX (box), icon);
+              if (!label)
+                gtk_widget_set_vexpand (icon, TRUE);
+            }
          if (label)
             gtk_box_pack_start (GTK_BOX (box), label);
        }