Fix debugger-related issues in the code serializer.

src/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 1944 matching lines @@
       return;
     }
     // TODO(yangguo) figure out whether other code kinds can be handled smarter.
   }
 
   if (heap_object == source_) {
     SerializeSourceObject(how_to_code, where_to_point, skip);
     return;
   }
 
+  if (heap_object->IsScript()) {
+    // The wrapper cache uses a Foreign object to point to a global handle.
+    // However, the object visitor expects foreign objects to point to external
+    // references.  Clear the cache to avoid this issue.
+    Script::cast(heap_object)->ClearWrapperCache();
+  }
+
   if (skip != 0) {
     sink_->Put(kSkip, "SkipFromSerializeObject");
     sink_->PutInt(skip, "SkipDistanceFromSerializeObject");
   }
   // Object has not yet been serialized.  Serialize it here.
   ObjectSerializer serializer(this, heap_object, sink_, how_to_code,
                               where_to_point);
   serializer.Serialize();
 }
 
@@ skipping 86 matching lines @@
 
 int SerializedCodeData::CheckSum(String* string) {
   int checksum = Version::Hash();
 #ifdef DEBUG
   uint32_t seed = static_cast<uint32_t>(checksum);
   checksum = static_cast<int>(IteratingStringHasher::Hash(string, seed));
 #endif  // DEBUG
   return checksum;
 }
 } }  // namespace v8::internal