Revert "Replace HeapNumber as doublebox with an explicit MutableHeapNumber."

src/arm64/stub-cache-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.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/codegen.h"
 #include "src/ic-inl.h"
@@ skipping 381 matching lines @@
     __ SmiUntagToDouble(temp_double, value_reg, kSpeculativeUntag);
 
     Label do_store;
     __ JumpIfSmi(value_reg, &do_store);
 
     __ CheckMap(value_reg, scratch1, Heap::kHeapNumberMapRootIndex,
                 miss_label, DONT_DO_SMI_CHECK);
     __ Ldr(temp_double, FieldMemOperand(value_reg, HeapNumber::kValueOffset));
 
     __ Bind(&do_store);
-    __ AllocateHeapNumber(storage_reg, slow, scratch1, scratch2, temp_double,
-                          NoReg, MUTABLE);
+    __ AllocateHeapNumber(storage_reg, slow, scratch1, scratch2, temp_double);
   }
 
   // Stub never generated for non-global objects that require access checks.
   ASSERT(object->IsJSGlobalProxy() || !object->IsAccessCheckNeeded());
 
   // Perform map transition for the receiver if necessary.
   if ((details.type() == FIELD) &&
       (object->map()->unused_property_fields() == 0)) {
     // The properties must be extended before we can store the value.
     // We jump to a runtime call that extends the properties array.
@@ skipping 1061 matching lines @@
 
   // Miss case, call the runtime.
   __ Bind(&miss);
   TailCallBuiltin(masm, Builtins::kKeyedLoadIC_Miss);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM64