Using setVerticalScrollbarOrientation(EditorEx.VERTICAL_SCROLLBAR_LEFT) on editor from PsiAwareTextEditorImpl does not separate scrollbar from editor text

In my plugin I would like to have the scrollbar on the left hand side. I am accomplishing this by calling the following on textEditor (which is an instance of PsiAwareTextEditorImpl)

((EditorEx) textEditor.getEditor).setVerticalScrollbarOrientation(EditorEx.VERTICAL_SCROLLBAR_LEFT);

However, when I do this the scrolllbar is placed directly over the text (see attached image below)



However if instead I create a new editor as follows:

EditorFactory factory = EditorFactory.getInstance();

EditorEx editor = (EditorEx) factory.createEditor(document, project);

editor.setVerticalScrollbarOrientation(EditorEx.VERTICAL_SCROLLBAR_LEFT);

the resultant editor has the desired property of making the scrollbar seperate from the text (see attached image below)

How can I accomplish the same thing using the editor from the PisAwareTextEditorImpl directly.