Use wxUILocale for date formatting in wxDataViewDateRenderer

Use the appropriate format for the dates by using the UI, rather than C,
locale, similarly to wxGrid.

include/wx/dvrenderers.h

@@ -527,6 +527,8 @@ public:
     virtual wxSize GetSize() const wxOVERRIDE;
 
 private:
+    wxString FormatDate() const;
+
     wxDateTime    m_date;
 };
 #else // !wxUSE_DATEPICKCTRL

src/common/datavcmn.cpp

@@ -28,6 +28,8 @@
 #include "wx/choice.h"
 #include "wx/imaglist.h"
 #include "wx/renderer.h"
+#include "wx/uilocale.h"
+
 #if wxUSE_ACCESSIBILITY
     #include "wx/access.h"
 #endif // wxUSE_ACCESSIBILITY
@@ -1986,23 +1988,28 @@ bool wxDataViewDateRenderer::GetValue(wxVariant& value) const
     return true;
 }
 
+wxString wxDataViewDateRenderer::FormatDate() const
+{
+    return m_date.Format(wxGetUIDateFormat());
+}
+
 #if wxUSE_ACCESSIBILITY
 wxString wxDataViewDateRenderer::GetAccessibleDescription() const
 {
-    return m_date.FormatDate();
+    return FormatDate();
 }
 #endif // wxUSE_ACCESSIBILITY
 
 bool wxDataViewDateRenderer::Render(wxRect cell, wxDC* dc, int state)
 {
-    wxString tmp = m_date.FormatDate();
+    wxString tmp = FormatDate();
     RenderText( tmp, 0, cell, dc, state );
     return true;
 }
 
 wxSize wxDataViewDateRenderer::GetSize() const
 {
-    return GetTextExtent(m_date.FormatDate());
+    return GetTextExtent(FormatDate());
 }
 
 #endif // (defined(wxHAS_GENERIC_DATAVIEWCTRL) || defined(__WXGTK__)) && wxUSE_DATEPICKCTRL