Fix debugger-related issues in the code serializer.

src/serialize.cc

Index: src/serialize.cc
diff --git a/src/serialize.cc b/src/serialize.cc
index 4156dfbf626fef88ebe2ec6c55f84240bf8a869e..71bc363cf22830c65196df66c01e6eaeca603d3f 100644
--- a/src/serialize.cc
+++ b/src/serialize.cc
@@ -1962,6 +1962,13 @@ void CodeSerializer::SerializeObject(Object* o, HowToCode how_to_code,
     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");