Put preservation of optimized code map behind a flag.

src/objects-visiting-inl.h

Index: src/objects-visiting-inl.h
diff --git a/src/objects-visiting-inl.h b/src/objects-visiting-inl.h
index d0a70c3fbf4d921422e9215605511738439e05c1..f83f00fd5d139574a9ccc2a3ab9ae09456794f0d 100644
--- a/src/objects-visiting-inl.h
+++ b/src/objects-visiting-inl.h
@@ -311,6 +311,12 @@ void StaticMarkingVisitor<StaticVisitor>::VisitSharedFunctionInfo(
   if (shared->ic_age() != heap->global_ic_age()) {
     shared->ResetForNewContext(heap->global_ic_age());
   }
+  if (FLAG_cache_optimized_code &&
+      FLAG_flush_optimized_code_cache &&
+      !shared->optimized_code_map()->IsSmi()) {
+    // Always flush the optimized code map if requested by flag.
+    shared->ClearOptimizedCodeMap();
+  }
   MarkCompactCollector* collector = heap->mark_compact_collector();
   if (collector->is_code_flushing_enabled()) {
     if (FLAG_cache_optimized_code && !shared->optimized_code_map()->IsSmi()) {