Return MaybeHandle from Object::ToSmi.

src/objects.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_OBJECTS_H_
 #define V8_OBJECTS_H_
 
 #include "allocation.h"
 #include "assert-scope.h"
 #include "builtins.h"
@@ skipping 1472 matching lines @@
 
   // Convert to a JSObject if needed.
   // native_context is used when creating wrapper object.
   static inline MaybeHandle<JSReceiver> ToObject(Isolate* isolate,
                                                  Handle<Object> object);
   static MaybeHandle<JSReceiver> ToObject(Isolate* isolate,
                                           Handle<Object> object,
                                           Handle<Context> context);
 
   // Converts this to a Smi if possible.
-  // Failure is returned otherwise.
-  static MUST_USE_RESULT inline Handle<Object> ToSmi(Isolate* isolate,
-                                                     Handle<Object> object);
+  static MUST_USE_RESULT inline MaybeHandle<Smi> ToSmi(Isolate* isolate,
+                                                       Handle<Object> object);
 
   void Lookup(Name* name, LookupResult* result);
 
   MUST_USE_RESULT static MaybeHandle<Object> GetPropertyWithReceiver(
       Handle<Object> object,
       Handle<Object> receiver,
       Handle<Name> name,
       PropertyAttributes* attributes);
   MUST_USE_RESULT static inline MaybeHandle<Object> GetPropertyOrElement(
       Handle<Object> object,
@@ skipping 9688 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_