tdf#104334 DOC import: don't map STYLREF with switches to SwChapterField

Commit d635b351 (tdf#99100 DOC import:
handle subset of STYLEREF natively, 2016-04-06) started to import the
STYLEREF field code as SwChapterField in case it had \[a-z] switches
after the field argument.

The bugdoc has a \s switch, which is not documented in ISO/IEC
29500-1:2012 17.16.5.59 "STYLEREF", nor is really clear what it would
do.

The original use-case was for the " STYLEREF 1 \* MERGEFORMAT " syntax,
so just keep using fieldmarks for the " STYLEREF <field argument> \[a-z]
" case.

Change-Id: Ibd094e72be4e179c779a79a75769b599d4d9bba8
Reviewed-on: https://gerrit.libreoffice.org/33489Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Jenkins <ci@libreoffice.org>

sw/qa/extras/ww8export/ww8export2.cxx

@@ -74,6 +74,14 @@ DECLARE_WW8EXPORT_TEST(testTdf104805, "tdf104805.doc")
     }
 }
 
+DECLARE_WW8EXPORT_TEST(testTdf104334, "tdf104334.doc")
+{
+    // This failed with a container::NoSuchElementException: STYLEREF was
+    // mapped to SwChapterField, and the field result was "This is a Heading 1"
+    // instead of just "1".
+    CPPUNIT_ASSERT_EQUAL(OUString("1"), getRun(getParagraph(2), 3)->getString());
+}
+
 CPPUNIT_PLUGIN_IMPLEMENT();
 
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */

sw/source/filter/ww8/ww8par5.cxx

@@ -914,6 +914,14 @@ long SwWW8ImplReader::Read_Field(WW8PLCFManResult* pRes)
         if (nRet == -2 && !aReadParam.GetResult().isEmpty())
             // Single numeric argument: this can be handled by SwChapterField.
             bHasHandler = rtl::isAsciiDigit(aReadParam.GetResult()[0]);
+
+        if (bHasHandler)
+        {
+            nRet = aReadParam.SkipToNextToken();
+            // Handle using SwChapterField only in case there is no \[a-z]
+            // switch after the field argument.
+            bHasHandler = nRet < 0 || nRet == '*';
+        }
     }
 
     // keine Routine vorhanden