Hydrogenize (and share) part of StoreTransition handler as a StoreTransitionStub.

src/interface-descriptors.h

 // Copyright 2014 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_CALL_INTERFACE_DESCRIPTOR_H_
 #define V8_CALL_INTERFACE_DESCRIPTOR_H_
 
 #include "src/assembler.h"
 #include "src/macro-assembler.h"
 
 namespace v8 {
 namespace internal {
 
 class PlatformInterfaceDescriptor;
 
 #define INTERFACE_DESCRIPTOR_LIST(V)          \
   V(Load)                                     \
   V(Store)                                    \
-  V(ExtendStorage)                            \
+  V(StoreTransition)                          \
   V(ElementTransitionAndStore)                \
   V(Instanceof)                               \
   V(VectorLoadICTrampoline)                   \
   V(VectorLoadIC)                             \
   V(FastNewClosure)                           \
   V(FastNewContext)                           \
   V(ToNumber)                                 \
   V(NumberToString)                           \
   V(FastCloneShallowArray)                    \
   V(FastCloneShallowObject)                   \
@@ skipping 177 matching lines @@
     kNameIndex,
     kValueIndex,
     kParameterCount
   };
   static const Register ReceiverRegister();
   static const Register NameRegister();
   static const Register ValueRegister();
 };
 
 
-class ExtendStorageDescriptor : public StoreDescriptor {
+class StoreTransitionDescriptor : public StoreDescriptor {
  public:
-  DECLARE_DESCRIPTOR(ExtendStorageDescriptor, StoreDescriptor)
+  DECLARE_DESCRIPTOR(StoreTransitionDescriptor, StoreDescriptor)
 
   // Extends StoreDescriptor with Map parameter.
   enum ParameterIndices {
     kReceiverIndex,
     kNameIndex,
     kValueIndex,
     kMapIndex,
     kParameterCount
   };
   static const Register MapRegister();
@@ skipping 264 matching lines @@
 }  // namespace v8::internal
 
 
 #if V8_TARGET_ARCH_ARM64
 #include "src/arm64/interface-descriptors-arm64.h"
 #elif V8_TARGET_ARCH_ARM
 #include "src/arm/interface-descriptors-arm.h"
 #endif
 
 #endif  // V8_CALL_INTERFACE_DESCRIPTOR_H_