Add FX_OVERRIDE and use it for virtual functions of FX_FINAL classes.

core/src/fxge/apple/apple_int.h

Index: core/src/fxge/apple/apple_int.h
diff --git a/core/src/fxge/apple/apple_int.h b/core/src/fxge/apple/apple_int.h
index a8fbe2fbaaaa14485c38be1654d1c5ff0f7b754b..e3794159b81a144c9098f7e70c2c84ce6b48ceff 100644
--- a/core/src/fxge/apple/apple_int.h
+++ b/core/src/fxge/apple/apple_int.h
@@ -188,25 +188,25 @@ protected:
 class CFX_FontProvider FX_FINAL : public IFX_FileRead
 {
 public:
-    virtual void			Release()
+    virtual void			Release() FX_OVERRIDE
     {
         delete this;
     }
-    virtual FX_FILESIZE		GetSize()
+    virtual FX_FILESIZE		GetSize() FX_OVERRIDE
     {
         return (FX_FILESIZE)_totalSize;
     }
-    virtual FX_BOOL			ReadBlock(void* buffer, FX_FILESIZE offset, size_t size);
+    virtual FX_BOOL			ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) FX_OVERRIDE;
 
-    virtual FX_BOOL			IsEOF()
+    virtual FX_BOOL			IsEOF() FX_OVERRIDE
     {
         return _offSet == _totalSize;
     }
-    virtual FX_FILESIZE		GetPosition()
+    virtual FX_FILESIZE		GetPosition() FX_OVERRIDE
     {
         return (FX_FILESIZE)_offSet;
     }
-    virtual size_t			ReadBlock(void* buffer, size_t size);
+    virtual size_t			ReadBlock(void* buffer, size_t size) FX_OVERRIDE;
 public:
     CFX_FontProvider(CGFontRef cgFont);
     ~CFX_FontProvider();