Fix remaining -Wdelete-non-virtual-dtor violations on Windows.

core/src/fxge/win32/fx_win32_dwrite.cpp

Index: core/src/fxge/win32/fx_win32_dwrite.cpp
diff --git a/core/src/fxge/win32/fx_win32_dwrite.cpp b/core/src/fxge/win32/fx_win32_dwrite.cpp
index 0326798ec32259a8d58645fdb3ef21409e0259a7..2b32d572b5374bce99ec90781378ee38042da29d 100644
--- a/core/src/fxge/win32/fx_win32_dwrite.cpp
+++ b/core/src/fxge/win32/fx_win32_dwrite.cpp
@@ -26,7 +26,7 @@ inline InterfaceType* SafeAcquire(InterfaceType* newObject)
     }
     return newObject;
 }
-class CDwFontFileStream : public IDWriteFontFileStream, public CFX_Object
+class CDwFontFileStream FX_FINAL : public IDWriteFontFileStream, public CFX_Object
 {
 public:
     explicit CDwFontFileStream(void const* fontFileReferenceKey, UINT32 fontFileReferenceKeySize);
@@ -46,7 +46,7 @@ private:
     void const* resourcePtr_;
     DWORD resourceSize_;
 };
-class CDwFontFileLoader : public IDWriteFontFileLoader, public CFX_Object
+class CDwFontFileLoader FX_FINAL : public IDWriteFontFileLoader, public CFX_Object
 {
 public:
     virtual HRESULT STDMETHODCALLTYPE QueryInterface(REFIID iid, void** ppvObject);