[gnome-builder/wip/gtk4-port] plugins/buildui: allow clearing build target selections

[Christian Hergert <chergert src gnome org>]

commit 3ecff98dd0d35a0f4c236e0ac271866eb696f9e4
Author: Christian Hergert <chergert redhat com>
Date:   Tue May 10 11:50:10 2022 -0700

    plugins/buildui: allow clearing build target selections

 src/plugins/buildui/gbp-buildui-targets-dialog.ui | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
---
diff --git a/src/plugins/buildui/gbp-buildui-targets-dialog.ui 
b/src/plugins/buildui/gbp-buildui-targets-dialog.ui
index 4d47adbe3..1e535bcc6 100644
--- a/src/plugins/buildui/gbp-buildui-targets-dialog.ui
+++ b/src/plugins/buildui/gbp-buildui-targets-dialog.ui
@@ -22,8 +22,25 @@
                     <property name="spinning" bind-source="GbpBuilduiTargetsDialog" bind-property="busy" 
bind-flags="sync-create"/>
                   </object>
                 </property>
+                <child>
+                  <object class="AdwActionRow">
+                    <property name="title" translatable="yes">Build System Default</property>
+                    <property name="activatable-widget">default_target</property>
+                    <child type="suffix">
+                      <object class="GtkCheckButton" id="default_target">
+                        <property name="action-name">build-manager.default-build-target</property>
+                        <property name="action-target">''</property>
+                        <style>
+                          <class name="checkimage"/>
+                        </style>
+                      </object>
+                    </child>
+                  </object>
+                </child>
                 <child>
                   <object class="GtkListBox" id="list_box">
+                    <property name="margin-top">12</property>
+                    <property name="selection-mode">none</property>
                     <style>
                       <class name="boxed-list"/>
                     </style>