[serializer] small fixes for blink snapshot.

src/address-map.cc

 // Copyright 2015 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/address-map.h"
 #include "src/heap/heap.h"
 #include "src/isolate.h"
 #include "src/objects-inl.h"
 
 namespace v8 {
 namespace internal {
 
 RootIndexMap::RootIndexMap(Isolate* isolate) {
   map_ = isolate->root_index_map();
   if (map_ != NULL) return;
-  map_ = new base::HashMap();
+  map_ = new HeapObjectToIndexHashMap();
   for (uint32_t i = 0; i < Heap::kStrongRootListLength; i++) {
     Heap::RootListIndex root_index = static_cast<Heap::RootListIndex>(i);
     Object* root = isolate->heap()->root(root_index);
     if (!root->IsHeapObject()) continue;
     // Omit root entries that can be written after initialization. They must
     // not be referenced through the root list in the snapshot.
     if (isolate->heap()->RootCanBeTreatedAsConstant(root_index)) {
       HeapObject* heap_object = HeapObject::cast(root);
-      base::HashMap::Entry* entry = LookupEntry(map_, heap_object, false);
-      if (entry != NULL) {
+      if (map_->Has(heap_object)) {
         // Some are initialized to a previous value in the root list.
-        DCHECK_LT(GetValue(entry), i);
+        DCHECK_LT(map_->Get(heap_object), i);
       } else {
-        SetValue(LookupEntry(map_, heap_object, true), i);
+        map_->Set(heap_object, i);
       }
     } else {
       // Immortal immovable root objects are constant and allocated on the first
       // page of old space. Non-constant roots cannot be immortal immovable. The
       // root index map contains all immortal immmovable root objects.
       CHECK(!Heap::RootIsImmortalImmovable(root_index));
     }
   }
   isolate->set_root_index_map(map_);
 }
 
 }  // namespace internal
 }  // namespace v8