DEFINE_STATIC_LOCAL(): assert against illegal use of GCed types.

third_party/WebKit/Source/wtf/TypeTraits.h

Index: third_party/WebKit/Source/wtf/TypeTraits.h
diff --git a/third_party/WebKit/Source/wtf/TypeTraits.h b/third_party/WebKit/Source/wtf/TypeTraits.h
index 1d938b5ce4c18f34536e59786a52cff0669085a0..002ec4fd6e6cfdf5a29c27cb7c7866052b3b6082 100644
--- a/third_party/WebKit/Source/wtf/TypeTraits.h
+++ b/third_party/WebKit/Source/wtf/TypeTraits.h
@@ -228,6 +228,19 @@ public:
 };
 
 template<typename T>
+class IsPersistentReferenceType {
+    typedef char YesType;
+    typedef struct NoType {
+        char padding[8];
+    } NoType;
+
+    template <typename U> static YesType checkPersistentReferenceType(typename U::IsPersistentReferenceTypeMarker*);
+    template <typename U> static NoType checkPersistentReferenceType(...);
+public:
+    static const bool value = (sizeof(YesType) == sizeof(checkPersistentReferenceType<T>(nullptr)));
+};
+
+template<typename T>
 class IsPointerToGarbageCollectedType {
 public:
     static const bool value = false;