adding back button

public/app/features/dashboard/dashgrid/PanelEditor.tsx

@@ -87,6 +87,9 @@ export class PanelEditor extends PureComponent<PanelEditorProps> {
 
     return (
       <div className="panel-editor-container__editor">
+        <div className="panel-editor__close">
+          <i className="fa fa-arrow-left" />
+        </div>
         {
           // <div className="panel-editor-resizer">
           //   <div className="panel-editor-resizer__handle">

public/sass/components/_panel_editor.scss

@@ -40,6 +40,24 @@
   box-shadow: $popover-shadow;
 }
 
+.panel-editor__close {
+  @include buttonBackground($btn-inverse-bg, $btn-inverse-bg-hl);
+  position: absolute;
+  left: 11px;
+  top: 5px;
+  width: 40px;
+  height: 40px;
+  border-radius: 50%;
+  display: flex;
+  align-items: center;
+
+  i {
+    flex-grow: 1;
+    text-align: center;
+    font-size: 20px;
+  }
+}
+
 .panel-editor__scroll {
   flex-grow: 1;
   min-width: 0;