Revert of [heap] Unify the immortal immovable root detection mechanism.

src/snapshot/serialize.cc

 // 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.
 
 #include "src/v8.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/base/platform/platform.h"
 #include "src/bootstrapper.h"
@@ skipping 1916 matching lines @@
   while (current < end) {
     while (current < end && (*current)->IsSmi()) current++;
     if (current < end) OutputRawData(reinterpret_cast<Address>(current));
 
     while (current < end && !(*current)->IsSmi()) {
       HeapObject* current_contents = HeapObject::cast(*current);
       int root_index = serializer_->root_index_map()->Lookup(current_contents);
       // Repeats are not subject to the write barrier so we can only use
       // immortal immovable root members. They are never in new space.
       if (current != start && root_index != RootIndexMap::kInvalidRootIndex &&
-          Heap::RootIsImmortalImmovable(
-              static_cast<Heap::RootListIndex>(root_index)) &&
+          Heap::RootIsImmortalImmovable(root_index) &&
           current_contents == current[-1]) {
         DCHECK(!serializer_->isolate()->heap()->InNewSpace(current_contents));
         int repeat_count = 1;
         while (&current[repeat_count] < end - 1 &&
                current[repeat_count] == current_contents) {
           repeat_count++;
         }
         current += repeat_count;
         bytes_processed_so_far_ += repeat_count * kPointerSize;
         if (repeat_count > kNumberOfFixedRepeat) {
@@ skipping 742 matching lines @@
   SerializedCodeData* scd = new SerializedCodeData(cached_data);
   SanityCheckResult r = scd->SanityCheck(isolate, source);
   if (r == CHECK_SUCCESS) return scd;
   cached_data->Reject();
   source->GetIsolate()->counters()->code_cache_reject_reason()->AddSample(r);
   delete scd;
   return NULL;
 }
 }  // namespace internal
 }  // namespace v8