Fixes issues following merge with 'dev'

- External Editor: App icon not correctly managed in RTImage
- Favorite preferences: Fixes widget sizes
- Other fix: With some versions of Glib/Glibmm library on MacOS, Glib::KeyFile "load_from_file" function does not raise a Glib::Error but another exception. This causes crash opening preferences panel due to missing dynamic profiles configuration

rtgui/externaleditorpreferences.cc

@@ -92,8 +92,8 @@ ExternalEditorPreferences::getEditors() const
     auto children = list_model->children();
 
     for (auto rowIter = children.begin(); rowIter != children.end(); rowIter++) {
-        const Gio::Icon *const icon = rowIter->get_value(model_columns.icon).get();
-        const auto &icon_serialized = icon == nullptr ? "" : icon->serialize().print();
+        const auto icon = rowIter->get_value(model_columns.icon);
+        const auto &icon_serialized = !icon ? "" : icon->serialize().print();
         editors.push_back(ExternalEditorPreferences::EditorInfo(
                               rowIter->get_value(model_columns.name),
                               rowIter->get_value(model_columns.command),

rtgui/rtimage.cc

@@ -74,7 +74,7 @@ RTImage::RTImage (const Glib::RefPtr<const Gio::Icon>& gIcon, const Gtk::IconSiz
     Gtk::Image(),
     size(iconSize),
     icon_name(""),
-    g_icon(Glib::RefPtr<const Gio::Icon>())
+    g_icon(gIcon)
 {
     // Configure RTImage based on g_icon
     set(this->g_icon, this->size);

rtgui/toollocationpref.cc

@@ -734,7 +734,7 @@ ToolLocationPreference::ToolLocationPreference(Options &options) :
     Gtk::Box *favorites_box = Gtk::manage(new Gtk::Box());
     Gtk::ScrolledWindow *favorites_list_scrolled_window =
         Gtk::manage(new Gtk::ScrolledWindow());
-    favorites_list_scrolled_window->set_min_content_width(RTScalable::scalePixelSize(300));
+    favorites_list_scrolled_window->set_min_content_width(RTScalable::scalePixelSize(400));
     layout_grid->attach_next_to(*favorites_frame, Gtk::PositionType::POS_RIGHT, 1, 1);
     favorites_box->pack_start(impl->favoritesListEditButtons, false, false);
     favorites_box->pack_start(*favorites_list_scrolled_window, false, false);