[stubs] Drop CallApiCallbackStub::call_data_undefined optimization.

src/arm64/code-stubs-arm64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/api-arguments.h"
 #include "src/arm64/assembler-arm64-inl.h"
 #include "src/arm64/frames-arm64.h"
 #include "src/arm64/macro-assembler-arm64-inl.h"
@@ skipping 3013 matching lines @@
   __ PushRoot(Heap::kUndefinedValueRootIndex);
 
   // context, callee and call data.
   __ Push(context, callee, call_data);
 
   if (!is_lazy()) {
     // Load context from callee
     __ Ldr(context, FieldMemOperand(callee, JSFunction::kContextOffset));
   }
 
-  if (!call_data_undefined()) {
-    __ LoadRoot(call_data, Heap::kUndefinedValueRootIndex);
-  }
+  __ LoadRoot(call_data, Heap::kUndefinedValueRootIndex);
   Register isolate_reg = x5;
   __ Mov(isolate_reg, ExternalReference::isolate_address(masm->isolate()));
 
   // FunctionCallbackArguments:
   //    return value, return value default, isolate, holder.
   __ Push(call_data, call_data, isolate_reg, holder);
 
   // Prepare arguments.
   Register args = x6;
   __ Mov(args, masm->StackPointer());
@@ skipping 116 matching lines @@
                            kStackUnwindSpace, NULL, spill_offset,
                            return_value_operand, NULL);
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM64