Verify that code stubs and full code do not have pointers that can retain

src/code-stubs.cc

Index: src/code-stubs.cc
diff --git a/src/code-stubs.cc b/src/code-stubs.cc
index 895569d41357ca34acea2c232dc406044a8cd64d..3a15fdaabc162c341999b9a9954950259b85b283 100644
--- a/src/code-stubs.cc
+++ b/src/code-stubs.cc
@@ -81,6 +81,9 @@ void CodeStub::RecordCodeGeneration(Handle<Code> code) {
           CodeCreateEvent(Logger::STUB_TAG, *code, os.str().c_str()));
   Counters* counters = isolate()->counters();
   counters->total_stubs_code_size()->Increment(code->instruction_size());
+#ifdef DEBUG
+  code->VerifyEmbeddedObjects();
+#endif
 }