Return failure when allocating maps fails.

R=mstarzinger@chromium.org

Review URL: https://chromiumcodereview.appspot.com/14707011

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14626 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/objects.cc

@@ -2588,6 +2588,7 @@ MaybeObject* Map::GeneralizeRepresentation(int modify_index,
       // during GC. Its descriptor array is too large, but it will be
       // overwritten during retry anyway.
       Handle<Map>(new_map);
+      return maybe_map;
     }
   }