Context click should add a class to tree item (#3619)

* add ability to pass onDestroy callback to menu api show

* fix lint issues

* remove fdescribe

* rename event and variables to contextClickActive

* rename variable to active

* Sanding and polishing CSS related to context-click visual feedback

- Changed CSS `border` approach to `box-shadow` to avoid jumping;
- Removed unwired code and CSS styles for Folder grid and list views;

Co-authored-by: Jamie V <jamie.j.vigliotta@nasa.gov>
Co-authored-by: charlesh88 <charlesh88@gmail.com>

src/ui/layout/mct-tree.scss

@@ -95,6 +95,10 @@
                 color: $colorItemTreeSelectedFg;
             }
         }
+
+        &.is-context-clicked {
+            box-shadow: inset $colorItemTreeSelectedBg 0 0 0 1px;
+        }
     }
 }