[layout] Don't call clear_output() before pause-func

src/hb-ot-layout.cc

diff --git a/src/hb-ot-layout.cc b/src/hb-ot-layout.cc
index 257cc91..379d92e 100644
--- a/src/hb-ot-layout.cc
+++ b/src/hb-ot-layout.cc
@@ -1942,10 +1942,7 @@
     }
 
     if (stage->pause_func)
-    {
-      buffer->clear_output ();
       stage->pause_func (plan, font, buffer);
-    }
   }
 }