first phase of transition to unified Unicode build:

1. changed c_str() to return wxCStrData (implicitly convertible to wxChar*)
2. added template type-safe wrappers for vararg functions
3. added wxUniChar class representing single Unicode character
4. changed wxString::operator[] and wxString::iterator to return wxUniChar


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@44865 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/richtext/richtextbuffer.cpp

@@ -8201,8 +8201,8 @@ bool wxRichTextImageBlock::ReadHex(wxInputStream& stream, int length, int imageT
     int i;
     for (i = 0; i < dataSize; i ++)
     {
-        str[0] = stream.GetC();
-        str[1] = stream.GetC();
+        str[0] = (char)stream.GetC();
+        str[1] = (char)stream.GetC();
 
         m_data[i] = (unsigned char)wxHexToDec(str);
     }