Use explicit push-argument for InstanceSetter instruction.

vm/intermediate_language_x64.cc

Index: vm/intermediate_language_x64.cc
===================================================================
--- vm/intermediate_language_x64.cc	(revision 10115)
+++ vm/intermediate_language_x64.cc	(working copy)
@@ -2150,9 +2150,7 @@
     // Otherwise polymorphic dispatch.
   }
   // Call.
-  LocationSummary* result = new LocationSummary(0, 0, LocationSummary::kCall);
-  result->set_out(Location::RegisterLocation(RAX));
-  return result;
+  return Computation::MakeCallSummary();
 }