[hb-old] Adjust mark positioning parameters

Fallback mark positioning works now...  With hb-ft and hb-view /
hb-shape at least.

src/hb-old.cc

@@ -149,12 +149,12 @@ hb_old_getGlyphMetrics (HB_Font old_font,
 
   hb_font_get_glyph_extents (font, glyph, &extents);
 
-  metrics->xOffset = extents.x_bearing;
-  metrics->yOffset = extents.y_bearing;
+  metrics->x       = extents.x_bearing;
+  metrics->y       = extents.y_bearing;
   metrics->width   = extents.width;
-  metrics->height  = extents.height;
-  metrics->x       = hb_font_get_glyph_h_advance (font, glyph);
-  metrics->y       = 0;
+  metrics->height  = -extents.height;
+  metrics->xOffset = hb_font_get_glyph_h_advance (font, glyph);
+  metrics->yOffset = 0;
 }
 
 static HB_Fixed

src/hb-old/harfbuzz-shaper.cpp

@@ -63,6 +63,7 @@ static inline void positionCluster(HB_ShaperItem *item, int gfrom,  int glast)
         offsetBase += HB_FIXED_CONSTANT(4);
     else
         offsetBase += size;
+    offsetBase = -offsetBase;
     //qreal offsetBase = (size - 4) / 4 + qMin<qreal>(size, 4) + 1;
 //     qDebug("offset = %f", offsetBase);