tdf#42982 Make UNO error reporting more descriptive

Change-Id: Iea5527ec88778f573b2e03ccd069142b7493c63c
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/87650
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@cib.de>
diff --git a/vbahelper/source/msforms/vbanewfont.cxx b/vbahelper/source/msforms/vbanewfont.cxx
index 2e7e1ef..b966d84 100644
--- a/vbahelper/source/msforms/vbanewfont.cxx
+++ b/vbahelper/source/msforms/vbanewfont.cxx
@@ -71,7 +71,7 @@ void SAL_CALL VbaNewFont::setCharset( sal_Int16 nCharset )
    if( (0 <= nCharset) && (nCharset <= SAL_MAX_UINT8) )
        eFontEnc = rtl_getTextEncodingFromWindowsCharset( static_cast< sal_uInt8 >( nCharset ) );
    if( eFontEnc == RTL_TEXTENCODING_DONTKNOW )
        throw uno::RuntimeException();
        throw uno::RuntimeException("an unknown or missing encoding");
    mxProps->setPropertyValue( "FontCharset" , uno::Any( static_cast< sal_Int16 >( eFontEnc ) ) );
}