[Object.observe] Don't force normalization of elements for observed objects

src/objects-debug.cc

Index: src/objects-debug.cc
diff --git a/src/objects-debug.cc b/src/objects-debug.cc
index 6ab2ddffe2a9e0ea3772163e20e87bd269f1a7e0..80610c6a8b5de272099591d1bff2b688be818d5d 100644
--- a/src/objects-debug.cc
+++ b/src/objects-debug.cc
@@ -366,9 +366,6 @@ void Map::MapVerify() {
     SLOW_ASSERT(transitions()->IsSortedNoDuplicates());
     SLOW_ASSERT(transitions()->IsConsistentWithBackPointers(this));
   }
-  ASSERT(!is_observed() || instance_type() < FIRST_JS_OBJECT_TYPE ||
-         instance_type() > LAST_JS_OBJECT_TYPE ||
-         has_slow_elements_kind() || has_external_array_elements());
 }