Revert of Replace all remaining Oddball checks with new function

src/api.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_API_H_
 #define V8_API_H_
 
 #include "include/v8-testing.h"
 #include "src/contexts.h"
 #include "src/factory.h"
@@ skipping 263 matching lines @@
 #define DECLARE_OPEN_HANDLE(From, To) \
   static inline v8::internal::Handle<v8::internal::To> \
       OpenHandle(const From* that, bool allow_empty_handle = false);
 
 OPEN_HANDLE_LIST(DECLARE_OPEN_HANDLE)
 
 #undef DECLARE_OPEN_HANDLE
 
   template<class From, class To>
   static inline Local<To> Convert(v8::internal::Handle<From> obj) {
-    DCHECK(obj.is_null() ||
-           (obj->IsSmi() ||
-            !obj->IsTheHole(i::HeapObject::cast(*obj)->GetIsolate())));
+    DCHECK(obj.is_null() || !obj->IsTheHole());
     return Local<To>(reinterpret_cast<To*>(obj.location()));
   }
 
   template <class T>
   static inline v8::internal::Handle<v8::internal::Object> OpenPersistent(
       const v8::Persistent<T>& persistent) {
     return v8::internal::Handle<v8::internal::Object>(
         reinterpret_cast<v8::internal::Object**>(persistent.val_));
   }
 
@@ skipping 395 matching lines @@
   }
 
  private:
   static v8::Testing::StressType stress_type_;
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_API_H_