parseExternalDocName() also for ConventionXL_A1::parseAnyToken(), fdo#83481

to make 645bccf7 actually work for both,
ExcelA1 and ExcelR1C1 address conventions.

Change-Id: I5392dfb6a8ec6af784957181c722d519921fc065

sc/source/core/tool/compiler.cxx

@@ -1238,6 +1238,8 @@ struct ConventionXL_A1 : public Convention_A1, public ConventionXL
                                        sal_Int32 nSrcPos,
                                        const CharClass* pCharClass) const SAL_OVERRIDE
     {
+        ConventionXL::parseExternalDocName(rFormula, nSrcPos);
+
         ParseResult aRet;
         if ( lcl_isValidQuotedText(rFormula, nSrcPos, aRet) )
             return aRet;