fdo#52540, fdo#88051: fix Graphite layout

The previous fixes were incomplete solutions (see the new test
cases of the bug reports).

Change-Id: I928f09d94edf68d268de9046c16582e6f016d561

vcl/source/glyphs/graphite_layout.cxx

@@ -590,9 +590,12 @@ gr_segment * GraphiteLayout::CreateSegment(ImplLayoutArgs& rArgs)
         static com::sun::star::uno::Reference< com::sun::star::i18n::XCharacterClassification > xCharClass;
         if ( !xCharClass.is() )
             xCharClass = vcl::unohelper::CreateCharacterClassification();
-        size_t numchars2 = rArgs.mnEndCharPos - mnSegCharOffset; // fdo#52540, fdo#68313, fdo#70666 avoid bad ligature replacement
-        if (numchars > numchars2 && (rArgs.mpStr[numchars2] == '\t' || xCharClass->getType(rArgs.mpStr, numchars2 + 1) == ::com::sun::star::i18n::UnicodeType::LOWERCASE_LETTER))
+        size_t numchars2 = rArgs.mnEndCharPos - mnSegCharOffset; // fdo#52540, fdo#68313, fdo#70666 avoid bad ligature replacement, fdo#88051 layout problem
+        if (numchars > numchars2 && (rArgs.mpStr[mnSegCharOffset + numchars2] == '\t' ||
+            xCharClass->getType(rArgs.mpStr + mnSegCharOffset, numchars2 + 1) == ::com::sun::star::i18n::UnicodeType::LOWERCASE_LETTER))
+        {
             numchars = numchars2;
+        }
         if (mpFeatures)
             pSegment = gr_make_seg(mpFont, mpFace, 0, mpFeatures->values(), gr_utf16,
                                         rArgs.mpStr + mnSegCharOffset, numchars, bRtl);