Don't indent the expander column in list wxDataViewCtrl in wxOSX

Indenting the column contents to leave enough space for the expanders is
unnecessary in this case, so just don't do it.

Closes #17409.

docs/changes.txt

@@ -85,6 +85,7 @@ wxOSX:
 - Set up extensions filter correctly in wxFileDialog (nick863).
 - Turn off automatic quotes substitutions in wxTextCtrl (Xlord2).
 - Implement wxDataViewChoiceByIndexRenderer (wanup).
+- Fix unnecessary indentation in list-like wxDataViewCtrl (Andreas Falkenhahn).
 
 Unix:
 

src/osx/cocoa/dataview.mm

@@ -2239,6 +2239,15 @@ bool wxCocoaDataViewControl::AssociateModel(wxDataViewModel* model)
     else
         m_DataSource = NULL;
     [m_OutlineView setDataSource:m_DataSource]; // if there is a data source the data is immediately going to be requested
+
+    // By default, the first column is indented to leave enough place for the
+    // expanders, but this looks bad if there are no expanders, so don't use
+    // indent in this case.
+    if ( model && model->IsListModel() )
+    {
+        DoSetIndent(0);
+    }
+
     return true;
 }