Resolves: fdo#77831 use classic token rules for user-defined char (%foo)

Change-Id: Iebae064986ad722d445c8d654e39e338e104f021

starmath/qa/cppunit/test_nodetotextvisitors.cxx

@@ -232,6 +232,7 @@ void Test::SimpleOperators()
     parseandparseagain("llint a", "Double curved integral");
     parseandparseagain("lllint a", "Triple curved integral");
     parseandparseagain("prod from {i=1} to {n} {(i+1)}", "Product with range");
+    ParseAndCheck("%Ux2135", "%Ux2135", "fdo#77831");
 }
 
 void Test::SimpleAttributes()

starmath/source/parse.cxx

@@ -375,6 +375,12 @@ const sal_Int32 coContFlags =
     (coStartFlags & ~KParseTokens::IGNORE_LEADING_WS)
     | KParseTokens::TWO_DOUBLE_QUOTES_BREAK_STRING;
 
+// user-defined char continuing characters may be any alphanumeric or dot.
+const sal_Int32 coUserDefinedCharContFlags =
+    ((KParseTokens::ANY_LETTER_OR_NUMBER | KParseTokens::IGNORE_LEADING_WS | KParseTokens::ASC_DOT)
+        & ~KParseTokens::IGNORE_LEADING_WS)
+    | KParseTokens::TWO_DOUBLE_QUOTES_BREAK_STRING;
+
 // First character for numbers, may be any numeric or dot
 const sal_Int32 coNumStartFlags =
         KParseTokens::ASC_DIGIT |
@@ -644,7 +650,7 @@ void SmParser::NextToken()
                                 m_aBufferString, rnEndPos,
                                 KParseTokens::ANY_LETTER,
                                 aEmptyStr,
-                                coContFlags,
+                                coUserDefinedCharContFlags,
                                 aEmptyStr );
 
                         sal_Int32 nTmpStart = rnEndPos + aTmpRes.LeadingWhiteSpace;