[gnome-builder] symbol-tree: don't propagate natural size of menu button

[Christian Hergert <chergert src gnome org>]

commit 57acc177d75aed42ea9028bda42ccee61645ca4b
Author: Christian Hergert <chergert redhat com>
Date:   Tue Jul 4 15:12:54 2017 -0700

    symbol-tree: don't propagate natural size of menu button
    
    This makes sure we don't keep propagating the width of the label
    as a natural size for the pane. Doing so makes things
    unpredictable inside the multi-paned.

 plugins/symbol-tree/gbp-symbol-menu-button.ui |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/plugins/symbol-tree/gbp-symbol-menu-button.ui b/plugins/symbol-tree/gbp-symbol-menu-button.ui
index bf4316b..1363702 100644
--- a/plugins/symbol-tree/gbp-symbol-menu-button.ui
+++ b/plugins/symbol-tree/gbp-symbol-menu-button.ui
@@ -56,10 +56,11 @@
   <template class="GbpSymbolMenuButton" parent="GtkMenuButton">
     <property name="popover">popover</property>
     <child>
-      <object class="GtkBox">
+      <object class="DzlBox">
         <property name="margin-start">12</property>
         <property name="margin-end">12</property>
         <property name="spacing">6</property>
+        <property name="max-width-request">50</property>
         <property name="hexpand">true</property>
         <property name="visible">true</property>
         <child>