Added 'const' to the first argument to FT_Matrix_Multiply.

include/freetype/ftglyph.h

@@ -483,7 +483,7 @@ FT_BEGIN_HEADER
   /*    The result is undefined if either `a' or `b' is zero.              */
   /*                                                                       */
   FT_EXPORT( void )
-  FT_Matrix_Multiply( FT_Matrix*  a,
+  FT_Matrix_Multiply( const FT_Matrix*  a,
                       FT_Matrix*  b );
 
 

src/base/ftglyph.c

@@ -56,7 +56,7 @@
   /* documentation is in ftglyph.h */
 
   FT_EXPORT_DEF( void )
-  FT_Matrix_Multiply( FT_Matrix*  a,
+  FT_Matrix_Multiply( const FT_Matrix*  a,
                       FT_Matrix*  b )
   {
     FT_Fixed  xx, xy, yx, yy;