[gnome-usage] performace-view: Fix a double border when folded

[Adrien Plazas <aplazas src gnome org>]

commit 9d2bcd83d5ccacad17b3fe6bc7ec12ceff0c7c75
Author: Adrien Plazas <kekun plazas laposte net>
Date:   Fri Mar 19 09:00:38 2021 +0100

    performace-view: Fix a double border when folded
    
    This adds a separator and drops the sidebar's border, so the separator
    isn't part of the sidebar and is hence not visible when folded.

 data/interface/adwaita.css  |  6 +++++-
 data/ui/performance-view.ui | 12 ++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)
---
diff --git a/data/interface/adwaita.css b/data/interface/adwaita.css
index 6e0ba6c..f05e8f9 100644
--- a/data/interface/adwaita.css
+++ b/data/interface/adwaita.css
@@ -176,4 +176,8 @@ dzlstacklist list.stack-header {
     padding-bottom: 1px;
     margin: 0px;
     border:none;
-}
\ No newline at end of file
+}
+
+leaflet > box.sidebar {
+    border: none;
+}
diff --git a/data/ui/performance-view.ui b/data/ui/performance-view.ui
index b2868d1..7255c6d 100644
--- a/data/ui/performance-view.ui
+++ b/data/ui/performance-view.ui
@@ -26,6 +26,18 @@
           </object>
         </child>
 
+        <child>
+          <object class="GtkSeparator">
+            <property name="visible">True</property>
+            <style>
+              <class name="sidebar" />
+            </style>
+          </object>
+          <packing>
+            <property name="navigatable">False</property>
+          </packing>
+        </child>
+
         <child>
           <object class="GtkBox" id="content_box">
             <property name="visible">True</property>