Fix some out-of-line constant pool garbage collection bugs.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 17b92d0cc87e5d6258b551fb7bb534f8de76228c..4d59bdaf5ac9f38992991ec36472bb76574c9392 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -721,7 +721,6 @@ enum InstanceType {
   EXTERNAL_DOUBLE_ARRAY_TYPE,
   EXTERNAL_PIXEL_ARRAY_TYPE,  // LAST_EXTERNAL_ARRAY_TYPE
   FIXED_DOUBLE_ARRAY_TYPE,
-  CONSTANT_POOL_ARRAY_TYPE,
   FILLER_TYPE,  // LAST_DATA_TYPE
 
   // Structs.
@@ -752,6 +751,7 @@ enum InstanceType {
   BREAK_POINT_INFO_TYPE,
 
   FIXED_ARRAY_TYPE,
+  CONSTANT_POOL_ARRAY_TYPE,
   SHARED_FUNCTION_INFO_TYPE,
 
   JS_MESSAGE_OBJECT_TYPE,