Revert "Add Smi::Zero and replace all Smi::FromInt(0) calls"

src/runtime/runtime-regexp.cc

 // 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.
 
 #include "src/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/conversions-inl.h"
 #include "src/isolate-inl.h"
 #include "src/messages.h"
@@ skipping 688 matching lines @@
   int pattern_length = pattern->length();
   CHECK(pattern_length > 0);
 
   if (limit == 0xffffffffu) {
     FixedArray* last_match_cache_unused;
     Handle<Object> cached_answer(
         RegExpResultsCache::Lookup(isolate->heap(), *subject, *pattern,
                                    &last_match_cache_unused,
                                    RegExpResultsCache::STRING_SPLIT_SUBSTRINGS),
         isolate);
-    if (*cached_answer != Smi::kZero) {
+    if (*cached_answer != Smi::FromInt(0)) {
       // The cache FixedArray is a COW-array and can therefore be reused.
       Handle<JSArray> result = isolate->factory()->NewJSArrayWithElements(
           Handle<FixedArray>::cast(cached_answer));
       return *result;
     }
   }
 
   // The limit can be very large (0xffffffffu), but since the pattern
   // isn't empty, we can never create more parts than ~half the length
   // of the subject.
@@ skipping 300 matching lines @@
 
 
 RUNTIME_FUNCTION(Runtime_IsRegExp) {
   SealHandleScope shs(isolate);
   DCHECK(args.length() == 1);
   CONVERT_ARG_CHECKED(Object, obj, 0);
   return isolate->heap()->ToBoolean(obj->IsJSRegExp());
 }
 }  // namespace internal
 }  // namespace v8