[strong] Introduce strong bit

src/runtime/runtime.h

 // Copyright 2012 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_RUNTIME_RUNTIME_H_
 #define V8_RUNTIME_RUNTIME_H_
 
 #include "src/allocation.h"
 #include "src/objects.h"
 #include "src/zone.h"
@@ skipping 433 matching lines @@
   F(HasFastPackedElements, 1, 1)                     \
   F(ValueOf, 1, 1)                                   \
   F(SetValueOf, 2, 1)                                \
   F(JSValueGetValue, 1, 1)                           \
   F(HeapObjectGetMap, 1, 1)                          \
   F(MapGetInstanceType, 1, 1)                        \
   F(ObjectEquals, 2, 1)                              \
   F(IsObject, 1, 1)                                  \
   F(IsUndetectableObject, 1, 1)                      \
   F(IsSpecObject, 1, 1)                              \
+  F(IsStrong, 1, 1)                                  \
   F(ClassOf, 1, 1)                                   \
   F(DefineGetterPropertyUnchecked, 4, 1)             \
   F(DefineSetterPropertyUnchecked, 4, 1)
 
 
 #define FOR_EACH_INTRINSIC_OBSERVE(F)            \
   F(IsObserved, 1, 1)                            \
   F(SetIsObserved, 1, 1)                         \
   F(EnqueueMicrotask, 1, 1)                      \
   F(RunMicrotasks, 0, 1)                         \
@@ skipping 403 matching lines @@
 
 class DeclareGlobalsEvalFlag : public BitField<bool, 0, 1> {};
 class DeclareGlobalsNativeFlag : public BitField<bool, 1, 1> {};
 STATIC_ASSERT(LANGUAGE_END == 3);
 class DeclareGlobalsLanguageMode : public BitField<LanguageMode, 2, 2> {};
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_RUNTIME_RUNTIME_H_