Remove unused byte from Map::instance_sizes field.

src/arm64/macro-assembler-arm64.h

 // 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.
 
 #ifndef V8_ARM64_MACRO_ASSEMBLER_ARM64_H_
 #define V8_ARM64_MACRO_ASSEMBLER_ARM64_H_
 
 #include <vector>
 
 #include "src/bailout-reason.h"
@@ skipping 1287 matching lines @@
                 Label* gc_required,
                 AllocationFlags flags);
 
   void Allocate(int object_size,
                 Register result,
                 Register scratch1,
                 Register scratch2,
                 Label* gc_required,
                 AllocationFlags flags);
 
-  // Undo allocation in new space. The object passed and objects allocated after
-  // it will no longer be allocated. The caller must make sure that no pointers
-  // are left to the object(s) no longer allocated as they would be invalid when
-  // allocation is undone.
-  void UndoAllocationInNewSpace(Register object, Register scratch);
-
   void AllocateTwoByteString(Register result,
                              Register length,
                              Register scratch1,
                              Register scratch2,
                              Register scratch3,
                              Label* gc_required);
   void AllocateOneByteString(Register result, Register length,
                              Register scratch1, Register scratch2,
                              Register scratch3, Label* gc_required);
   void AllocateTwoByteConsString(Register result,
@@ skipping 974 matching lines @@
 #error "Unsupported option"
 #define CODE_COVERAGE_STRINGIFY(x) #x
 #define CODE_COVERAGE_TOSTRING(x) CODE_COVERAGE_STRINGIFY(x)
 #define __FILE_LINE__ __FILE__ ":" CODE_COVERAGE_TOSTRING(__LINE__)
 #define ACCESS_MASM(masm) masm->stop(__FILE_LINE__); masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 #endif  // V8_ARM64_MACRO_ASSEMBLER_ARM64_H_