[gnome-control-center] power: Use a HdyColumn

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 101ebf1bd43d209e088e1299f9709182b75bfa5c
Author: Adrien Plazas <kekun plazas laposte net>
Date:   Tue Jan 22 00:37:36 2019 +0100

    power: Use a HdyColumn
    
    This allows the window to reach narrower sizes.

 panels/power/cc-power-panel.ui | 30 +++++++-----------------------
 1 file changed, 7 insertions(+), 23 deletions(-)
---
diff --git a/panels/power/cc-power-panel.ui b/panels/power/cc-power-panel.ui
index b410285ed..35c29e8f6 100644
--- a/panels/power/cc-power-panel.ui
+++ b/panels/power/cc-power-panel.ui
@@ -118,30 +118,14 @@
         <property name="can_focus">False</property>
         <property name="hscrollbar_policy">never</property>
         <child>
-          <object class="GtkBox" id="main_box">
+          <object class="HdyColumn" id="main_box">
             <property name="visible">True</property>
-            <property name="can_focus">False</property>
-            <!-- Stub boxes to make the content cover 1/3 of the screen -->
-            <child>
-              <object class="GtkBox">
-                <property name="visible">True</property>
-                <property name="can_focus">False</property>
-                <property name="hexpand">True</property>
-              </object>
-            </child>
-
-            <child>
-              <object class="GtkBox">
-                <property name="visible">True</property>
-                <property name="can_focus">False</property>
-                <property name="hexpand">True</property>
-              </object>
-              <packing>
-                <property name="pack_type">end</property>
-              </packing>
-            </child>
-
-            <!-- Content -->
+            <property name="maximum_width">600</property>
+            <property name="linear_growth_width">400</property>
+            <property name="margin_top">32</property>
+            <property name="margin_bottom">32</property>
+            <property name="margin_start">12</property>
+            <property name="margin_end">12</property>
             <child>
               <object class="GtkBox" id="vbox_power">
                 <property name="visible">True</property>