--trace-hydrogen fix

R=verwaest@chromium.org

Review URL: https://codereview.chromium.org/141333006

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18670 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/hydrogen-instructions.cc

@@ -842,9 +842,7 @@ void HUnaryCall::PrintDataTo(StringStream* stream) {
 
 
 void HCallJSFunction::PrintDataTo(StringStream* stream) {
-  OperandAt(0)->PrintNameTo(stream);
-  stream->Add(" ");
-  OperandAt(1)->PrintNameTo(stream);
+  function()->PrintNameTo(stream);
   stream->Add(" ");
   stream->Add("#%d", argument_count());
 }