[gnome-text-editor] overview: add border to overview map

[Christian Hergert <chergert src gnome org>]

commit db541c9e3897387805e4680e2a807251d96dcb10
Author: Christian Hergert <chergert redhat com>
Date:   Sat Jun 19 14:33:45 2021 -0700

    overview: add border to overview map

 src/TextEditor.css | 7 +++++++
 src/editor-page.ui | 3 +++
 2 files changed, 10 insertions(+)
---
diff --git a/src/TextEditor.css b/src/TextEditor.css
index 47a0df5..61cef56 100644
--- a/src/TextEditor.css
+++ b/src/TextEditor.css
@@ -114,3 +114,10 @@ notebook:focus:backdrop {
   margin: 0px;
   padding: 3px;
 }
+
+textview.source-map:dir(ltr) {
+  border-left: 1px solid @borders;
+}
+textview.source-map:dir(rtl) {
+  border-right: 1px solid @borders;
+}
diff --git a/src/editor-page.ui b/src/editor-page.ui
index 6ea6511..2714f08 100644
--- a/src/editor-page.ui
+++ b/src/editor-page.ui
@@ -39,6 +39,9 @@
                     <property name="hexpand">false</property>
                     <property name="visible">false</property>
                     <property name="view">view</property>
+                    <style>
+                      <class name="source-map"/>
+                    </style>
                   </object>
                 </child>
               </object>