Oilpan: use template aliases for heap version of collections.

Source/platform/heap/Heap.h

Index: Source/platform/heap/Heap.h
diff --git a/Source/platform/heap/Heap.h b/Source/platform/heap/Heap.h
index 0268f0fb912f8dc1e2e4a0e3a706ca63030a40a6..cd7139b13625038d9a55e316786130b78149f663 100644
--- a/Source/platform/heap/Heap.h
+++ b/Source/platform/heap/Heap.h
@@ -1760,117 +1760,43 @@ public:
     }
 };
 
-// FIXME: These should just be template aliases:
-//
-// template<typename T, size_t inlineCapacity = 0>
-// using HeapVector = Vector<T, inlineCapacity, HeapAllocator>;
-//
-// as soon as all the compilers we care about support that.
-// MSVC supports it only in MSVC 2013.
 template<
     typename KeyArg,
     typename MappedArg,
     typename HashArg = typename DefaultHash<KeyArg>::Hash,
     typename KeyTraitsArg = HashTraits<KeyArg>,
     typename MappedTraitsArg = HashTraits<MappedArg> >
-class HeapHashMap : public HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg, HeapAllocator> { };
+using HeapHashMap = HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg, HeapAllocator>;
 
 template<
     typename ValueArg,
     typename HashArg = typename DefaultHash<ValueArg>::Hash,
     typename TraitsArg = HashTraits<ValueArg> >
-class HeapHashSet : public HashSet<ValueArg, HashArg, TraitsArg, HeapAllocator> { };
+using HeapHashSet = HashSet<ValueArg, HashArg, TraitsArg, HeapAllocator>;
 
 template<
     typename ValueArg,
     typename HashArg = typename DefaultHash<ValueArg>::Hash,
     typename TraitsArg = HashTraits<ValueArg> >
-class HeapLinkedHashSet : public LinkedHashSet<ValueArg, HashArg, TraitsArg, HeapAllocator> { };
+using HeapLinkedHashSet = LinkedHashSet<ValueArg, HashArg, TraitsArg, HeapAllocator>;
 
 template<
     typename ValueArg,
     size_t inlineCapacity = 0, // The inlineCapacity is just a dummy to match ListHashSet (off-heap).
     typename HashArg = typename DefaultHash<ValueArg>::Hash>
-class HeapListHashSet : public ListHashSet<ValueArg, inlineCapacity, HashArg, HeapListHashSetAllocator<ValueArg, inlineCapacity> > { };
+using HeapListHashSet = ListHashSet<ValueArg, inlineCapacity, HashArg, HeapListHashSetAllocator<ValueArg, inlineCapacity> >;
 
 template<
     typename Value,
     typename HashFunctions = typename DefaultHash<Value>::Hash,
     typename Traits = HashTraits<Value> >
-class HeapHashCountedSet : public HashCountedSet<Value, HashFunctions, Traits, HeapAllocator> { };
+using HeapHashCountedSet = HashCountedSet<Value, HashFunctions, Traits, HeapAllocator>;
 
 template<typename T, size_t inlineCapacity = 0>
-class HeapVector : public Vector<T, inlineCapacity, HeapAllocator> {
-public:
-    HeapVector() { }
-
-    explicit HeapVector(size_t size) : Vector<T, inlineCapacity, HeapAllocator>(size)
-    {
-    }
-
-    HeapVector(size_t size, const T& val) : Vector<T, inlineCapacity, HeapAllocator>(size, val)
-    {
-    }
-
-    template<size_t otherCapacity>
-    HeapVector(const HeapVector<T, otherCapacity>& other)
-        : Vector<T, inlineCapacity, HeapAllocator>(other)
-    {
-    }
-
-    template<typename U>
-    void append(const U& other)
-    {
-        Vector<T, inlineCapacity, HeapAllocator>::append(other);
-    }
-
-    template<typename U, size_t otherCapacity>
-    void appendVector(const HeapVector<U, otherCapacity>& other)
-    {
-        const Vector<U, otherCapacity, HeapAllocator>& otherVector = other;
-        Vector<T, inlineCapacity, HeapAllocator>::appendVector(otherVector);
-    }
-};
+using HeapVector = Vector<T, inlineCapacity, HeapAllocator>;
 
 template<typename T, size_t inlineCapacity = 0>
-class HeapDeque : public Deque<T, inlineCapacity, HeapAllocator> {
-public:
-    HeapDeque() { }
-
-    explicit HeapDeque(size_t size) : Deque<T, inlineCapacity, HeapAllocator>(size)
-    {
-    }
-
-    HeapDeque(size_t size, const T& val) : Deque<T, inlineCapacity, HeapAllocator>(size, val)
-    {
-    }
-
-    // FIXME: Doesn't work if there is an inline buffer, due to crbug.com/360572
-    HeapDeque<T, 0>& operator=(const HeapDeque& other)
-    {
-        HeapDeque<T> copy(other);
-        swap(copy);
-        return *this;
-    }
-
-    // FIXME: Doesn't work if there is an inline buffer, due to crbug.com/360572
-    inline void swap(HeapDeque& other)
-    {
-        Deque<T, inlineCapacity, HeapAllocator>::swap(other);
-    }
-
-    template<size_t otherCapacity>
-    HeapDeque(const HeapDeque<T, otherCapacity>& other)
-        : Deque<T, inlineCapacity, HeapAllocator>(other)
-    {
-    }
-
-    template<typename U>
-    void append(const U& other)
-    {
-        Deque<T, inlineCapacity, HeapAllocator>::append(other);
-    }
-};
+using HeapDeque = Deque<T, inlineCapacity, HeapAllocator>;
 
 template<typename T, size_t i>
 inline void swap(HeapVector<T, i>& a, HeapVector<T, i>& b) { a.swap(b); }
@@ -1946,21 +1872,6 @@ struct ThreadingTrait<HeapHashTableBacking<Table> > {
         && (ThreadingTrait<Value>::Affinity == MainThreadOnly) ? MainThreadOnly : AnyThread;
 };
 
-template<typename T, typename U, typename V, typename W, typename X>
-struct ThreadingTrait<HeapHashMap<T, U, V, W, X> > : public ThreadingTrait<HashMap<T, U, V, W, X, HeapAllocator> > { };
-
-template<typename T, typename U, typename V>
-struct ThreadingTrait<HeapHashSet<T, U, V> > : public ThreadingTrait<HashSet<T, U, V, HeapAllocator> > { };
-
-template<typename T, size_t inlineCapacity>
-struct ThreadingTrait<HeapVector<T, inlineCapacity> > : public ThreadingTrait<Vector<T, inlineCapacity, HeapAllocator> > { };
-
-template<typename T, size_t inlineCapacity>
-struct ThreadingTrait<HeapDeque<T, inlineCapacity> > : public ThreadingTrait<Deque<T, inlineCapacity, HeapAllocator> > { };
-
-template<typename T, typename U, typename V>
-struct ThreadingTrait<HeapHashCountedSet<T, U, V> > : public ThreadingTrait<HashCountedSet<T, U, V, HeapAllocator> > { };
-
 // The standard implementation of GCInfoTrait<T>::get() just returns a static
 // from the class T, but we can't do that for HashMap, HashSet, Vector, etc.
 // because they are in WTF and know nothing of GCInfos. Instead we have a
@@ -2499,21 +2410,6 @@ void HeapHashTableBacking<Table>::finalize(void* pointer)
     }
 }
 
-template<typename T, typename U, typename V, typename W, typename X>
-struct GCInfoTrait<HeapHashMap<T, U, V, W, X> > : public GCInfoTrait<HashMap<T, U, V, W, X, HeapAllocator> > { };
-template<typename T, typename U, typename V>
-struct GCInfoTrait<HeapHashSet<T, U, V> > : public GCInfoTrait<HashSet<T, U, V, HeapAllocator> > { };
-template<typename T, typename U, typename V>
-struct GCInfoTrait<HeapLinkedHashSet<T, U, V> > : public GCInfoTrait<LinkedHashSet<T, U, V, HeapAllocator> > { };
-template<typename T, size_t inlineCapacity, typename U>
-struct GCInfoTrait<HeapListHashSet<T, inlineCapacity, U> > : public GCInfoTrait<ListHashSet<T, inlineCapacity, U, HeapListHashSetAllocator<T, inlineCapacity> > > { };
-template<typename T, size_t inlineCapacity>
-struct GCInfoTrait<HeapVector<T, inlineCapacity> > : public GCInfoTrait<Vector<T, inlineCapacity, HeapAllocator> > { };
-template<typename T, size_t inlineCapacity>
-struct GCInfoTrait<HeapDeque<T, inlineCapacity> > : public GCInfoTrait<Deque<T, inlineCapacity, HeapAllocator> > { };
-template<typename T, typename U, typename V>
-struct GCInfoTrait<HeapHashCountedSet<T, U, V> > : public GCInfoTrait<HashCountedSet<T, U, V, HeapAllocator> > { };
-
 template<typename T>
 struct IfWeakMember;