added wxUniChar::AsUTF8() for easy conversion in UTF8 build

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@46376 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/stringops.cpp

@@ -190,13 +190,14 @@ bool wxStringOperationsUtf8::IsValidUtf8LeadByte(unsigned char c)
 #endif
 
 
-wxStringOperationsUtf8::Utf8CharBuffer
-wxStringOperationsUtf8::EncodeChar(const wxUniChar& ch)
+// NB: this is in this file and not unichar.cpp to keep all UTF-8 encoding
+//     code in single place
+wxUniChar::Utf8CharBuffer wxUniChar::AsUTF8() const
 {
     Utf8CharBuffer buf;
     char *out = buf.data;
 
-    wxUniChar::value_type code = ch.GetValue();
+    value_type code = GetValue();
 
     //    Char. number range   |        UTF-8 octet sequence
     //       (hexadecimal)     |              (binary)