Blink GC plugin: Ensure that classes with virtual trace methods always have vtables for their left-…

tools/clang/blink_gc_plugin/tests/non_virtual_trace.h

Index: tools/clang/blink_gc_plugin/tests/non_virtual_trace.h
diff --git a/tools/clang/blink_gc_plugin/tests/non_virtual_trace.h b/tools/clang/blink_gc_plugin/tests/non_virtual_trace.h
index a849a32057e7408db786ab4570bab92bcc483503..4179d49b6f42edfc56ec947c27155b92324961e5 100644
--- a/tools/clang/blink_gc_plugin/tests/non_virtual_trace.h
+++ b/tools/clang/blink_gc_plugin/tests/non_virtual_trace.h
@@ -22,6 +22,11 @@ public:
     void trace(Visitor*); // Cannot override a non-virtual trace.
 };
 
+class D : public B {
+public:
+    virtual void trace(Visitor*); // Cannot override a non-virtual trace.
+};
+
 }
 
 #endif