Revert "Improve hashCode for closure objects"

runtime/vm/dart_entry.cc

Index: runtime/vm/dart_entry.cc
diff --git a/runtime/vm/dart_entry.cc b/runtime/vm/dart_entry.cc
index fd91fb0b017106352f93bfeae2ebfe54131cb076..a59b9dff76940c458f3832f52b429d646d822a59 100644
--- a/runtime/vm/dart_entry.cc
+++ b/runtime/vm/dart_entry.cc
@@ -509,24 +509,6 @@ RawObject* DartLibraryCalls::Equals(const Instance& left,
   return result.raw();
 }
 
-// On success, returns a RawInstance.  On failure, a RawError.
-RawObject* DartLibraryCalls::IdentityHashCode(const Instance& object) {
-  const int kNumArguments = 1;
-  Thread* thread = Thread::Current();
-  Zone* zone = thread->zone();
-  const Library& libcore = Library::Handle(zone, Library::CoreLibrary());
-  ASSERT(!libcore.IsNull());
-  const Function& function = Function::Handle(
-      zone, libcore.LookupFunctionAllowPrivate(Symbols::identityHashCode()));
-  ASSERT(!function.IsNull());
-  const Array& args = Array::Handle(zone, Array::New(kNumArguments));
-  args.SetAt(0, object);
-  const Object& result =
-      Object::Handle(zone, DartEntry::InvokeFunction(function, args));
-  ASSERT(result.IsInstance() || result.IsError());
-  return result.raw();
-}
-
 RawObject* DartLibraryCalls::LookupHandler(Dart_Port port_id) {
   Thread* thread = Thread::Current();
   Zone* zone = thread->zone();