Introduce short external strings without pointer cache.

src/serialize.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 651 matching lines @@
   // valid object pointers.
   isolate_->set_serialize_partial_snapshot_cache_length(
       Isolate::kPartialSnapshotCacheCapacity);
   ASSERT_EQ(NULL, external_reference_decoder_);
   external_reference_decoder_ = new ExternalReferenceDecoder();
   isolate_->heap()->IterateStrongRoots(this, VISIT_ONLY_STRONG);
   isolate_->heap()->IterateWeakRoots(this, VISIT_ALL);
 
   isolate_->heap()->set_global_contexts_list(
       isolate_->heap()->undefined_value());
+
+  // Update data pointers to the external strings containing natives sources.
+  for (int i = 0; i < Natives::GetBuiltinsCount(); i++) {
+    Object* source = isolate_->heap()->natives_source_cache()->get(i);
+    if (!source->IsUndefined()) {
+      ExternalAsciiString::cast(source)->update_data_cache();
+    }
+  }
 }
 
 
 void Deserializer::DeserializePartial(Object** root) {
   isolate_ = Isolate::Current();
   // Don't GC while deserializing - just expand the heap.
   AlwaysAllocateScope always_allocate;
   // Don't use the free lists while deserializing.
   LinearAllocationScope allocate_linearly;
   if (external_reference_decoder_ == NULL) {
@@ skipping 875 matching lines @@
   for (int i = 0; i < Natives::GetBuiltinsCount(); i++) {
     Object* source = HEAP->natives_source_cache()->get(i);
     if (!source->IsUndefined()) {
       ExternalAsciiString* string = ExternalAsciiString::cast(source);
       typedef v8::String::ExternalAsciiStringResource Resource;
       const Resource* resource = string->resource();
       if (resource == *resource_pointer) {
         sink_->Put(kNativesStringResource, "NativesStringResource");
         sink_->PutSection(i, "NativesStringResourceEnd");
         bytes_processed_so_far_ += sizeof(resource);
-        string->clear_data_cache();
         return;
       }
     }
   }
   // One of the strings in the natives cache should match the resource.  We
   // can't serialize any other kinds of external strings.
   UNREACHABLE();
 }
 
 
@@ skipping 86 matching lines @@
       fullness_[space] = RoundUp(fullness_[space], Page::kPageSize);
     }
   }
   int allocation_address = fullness_[space];
   fullness_[space] = allocation_address + size;
   return allocation_address;
 }
 
 
 } }  // namespace v8::internal