Remove unused code from aot optimizer.

runtime/vm/aot_optimizer.cc

Index: runtime/vm/aot_optimizer.cc
diff --git a/runtime/vm/aot_optimizer.cc b/runtime/vm/aot_optimizer.cc
index f7c741dc11d73184e253f926d6c9d12792e71a75..25074516d074f0c4042effded046301a806dbc92 100644
--- a/runtime/vm/aot_optimizer.cc
+++ b/runtime/vm/aot_optimizer.cc
@@ -108,8 +108,6 @@ void AotOptimizer::ApplyClassIds() {
             VisitInstanceCall(call);
           }
         }
-      } else if (instr->IsPolymorphicInstanceCall()) {
-        SpecializePolymorphicInstanceCall(instr->AsPolymorphicInstanceCall());
       }
     }
     current_iterator_ = NULL;
@@ -268,37 +266,6 @@ const ICData& AotOptimizer::TrySpecializeICData(const ICData& ic_data,
 }
 
 
-void AotOptimizer::SpecializePolymorphicInstanceCall(
-    PolymorphicInstanceCallInstr* call) {
-  if (!FLAG_polymorphic_with_deopt) {
-    // Specialization adds receiver checks which can lead to deoptimization.
-    return;
-  }
-  if (!call->with_checks()) {
-    return;  // Already specialized.
-  }
-
-  const intptr_t receiver_cid =
-      call->PushArgumentAt(0)->value()->Type()->ToCid();
-  if (receiver_cid == kDynamicCid) {
-    return;  // No information about receiver was infered.
-  }
-
-  const ICData& ic_data = TrySpecializeICData(call->ic_data(), receiver_cid);
-  if (ic_data.raw() == call->ic_data().raw()) {
-    // No specialization.
-    return;
-  }
-
-  PolymorphicInstanceCallInstr* specialized =
-      new(Z) PolymorphicInstanceCallInstr(call->instance_call(),
-                                          ic_data,
-                                          /* with_checks = */ false,
-                                          /* complete = */ false);
-  call->ReplaceWith(specialized, current_iterator());
-}
-
-
 static BinarySmiOpInstr* AsSmiShiftLeftInstruction(Definition* d) {
   BinarySmiOpInstr* instr = d->AsBinarySmiOp();
   if ((instr != NULL) && (instr->op_kind() == Token::kSHL)) {