[gtkmm] ListStore and TreeStore demos: Avoid runtime warnings

[Kjell Ahlstedt <kjellahl src gnome org>]

commit bb9c7f446dcdbc764580579baabc5ad98588024d
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Sat Jun 26 11:30:22 2021 +0200

    ListStore and TreeStore demos: Avoid runtime warnings
    
    Avoid "Allocation width too small."

 demos/gtk-demo/example_treeview_liststore.cc |  4 ++--
 demos/gtk-demo/example_treeview_treestore.cc | 10 +++++-----
 2 files changed, 7 insertions(+), 7 deletions(-)
---
diff --git a/demos/gtk-demo/example_treeview_liststore.cc b/demos/gtk-demo/example_treeview_liststore.cc
index 10bd969d..a258833d 100644
--- a/demos/gtk-demo/example_treeview_liststore.cc
+++ b/demos/gtk-demo/example_treeview_liststore.cc
@@ -175,9 +175,9 @@ void Example_TreeView_ListStore::add_columns()
     int cols_count = m_TreeView.append_column_editable("Fixed?", m_columns.fixed);
     auto pColumn = m_TreeView.get_column(cols_count-1);
 
-    /* set this column to a fixed sizing (of 50 pixels) */
+    /* set this column to a fixed sizing (of 60 pixels) */
     pColumn->set_sizing(Gtk::TreeViewColumn::Sizing::FIXED);
-    pColumn->set_fixed_width(50);
+    pColumn->set_fixed_width(60);
     pColumn->set_clickable();
   }
 
diff --git a/demos/gtk-demo/example_treeview_treestore.cc b/demos/gtk-demo/example_treeview_treestore.cc
index 96e94e50..4cae6566 100644
--- a/demos/gtk-demo/example_treeview_treestore.cc
+++ b/demos/gtk-demo/example_treeview_treestore.cc
@@ -342,7 +342,7 @@ void Example_TreeView_TreeStore::add_columns()
       pColumn->add_attribute(pRenderer->property_activatable(), m_columns.world);
 
       pColumn->set_sizing(Gtk::TreeViewColumn::Sizing::FIXED);
-      pColumn->set_fixed_width(50);
+      pColumn->set_fixed_width(60);
       pColumn->set_clickable();
     }
   }
@@ -359,7 +359,7 @@ void Example_TreeView_TreeStore::add_columns()
       pColumn->add_attribute(pRenderer->property_visible(), m_columns.visible);
 
       pColumn->set_sizing(Gtk::TreeViewColumn::Sizing::FIXED);
-      pColumn->set_fixed_width(50);
+      pColumn->set_fixed_width(60);
       pColumn->set_clickable();
     }
   }
@@ -377,7 +377,7 @@ void Example_TreeView_TreeStore::add_columns()
       pColumn->add_attribute(pRenderer->property_activatable(), m_columns.world);
 
       pColumn->set_sizing(Gtk::TreeViewColumn::Sizing::FIXED);
-      pColumn->set_fixed_width(50);
+      pColumn->set_fixed_width(60);
       pColumn->set_clickable();
     }
   }
@@ -394,7 +394,7 @@ void Example_TreeView_TreeStore::add_columns()
       pColumn->add_attribute(pRenderer->property_visible(), m_columns.visible);
 
       pColumn->set_sizing(Gtk::TreeViewColumn::Sizing::FIXED);
-      pColumn->set_fixed_width(50);
+      pColumn->set_fixed_width(60);
       pColumn->set_clickable();
     }
   }
@@ -411,7 +411,7 @@ void Example_TreeView_TreeStore::add_columns()
       pColumn->add_attribute(pRenderer->property_visible(), m_columns.visible);
 
       pColumn->set_sizing(Gtk::TreeViewColumn::Sizing::FIXED);
-      pColumn->set_fixed_width(50);
+      pColumn->set_fixed_width(60);
       pColumn->set_clickable();
     }
   }