ASSERT that Visitor::mark is only called when inGC()

Source/wtf/HashTable.h

Index: Source/wtf/HashTable.h
diff --git a/Source/wtf/HashTable.h b/Source/wtf/HashTable.h
index 40d57616b4d1fc2e4fc315c7d71174d774f49cbb..3751f113b9fd53750e90ca9be43b1ecf2e7afdcf 100644
--- a/Source/wtf/HashTable.h
+++ b/Source/wtf/HashTable.h
@@ -1256,7 +1256,14 @@ template<typename Key, typename Value, typename Extractor, typename HashFunction
                         // At this stage calling trace can make no difference
                         // (everything is already traced), but we use the
                         // return value to remove things from the collection.
-                        if (TraceInCollectionTrait<WeakHandlingInCollections, WeakPointersActWeak, ValueType, Traits>::trace(visitor, *element)) {
+#if ENABLE(ASSERT)
+                        visitor->setAllowTraceForHashTableWeakProcessing(true);

[haraken, 2015/01/13 07:55:53]

Add a FIXME to remove this.

BTW, do you really need to special-case the following trace()? I guess that the
following trace does not call mark() at all, and thus we don't need to set the
AllowTraceForHashTableWeakProcessing flag.

[kouhei (in TOK), 2015/01/14 02:10:05]

Done.
This trace does call mark(). I'll try to remove this hack in near future.

+#endif
+                        bool elementIsDead = TraceInCollectionTrait<WeakHandlingInCollections, WeakPointersActWeak, ValueType, Traits>::trace(visitor, *element);
+#if ENABLE(ASSERT)
+                        visitor->setAllowTraceForHashTableWeakProcessing(false);
+#endif
+                        if (elementIsDead) {
                             table->registerModification();
                             HashTableType::deleteBucket(*element); // Also calls the destructor.
                             table->m_deletedCount++;