Add allocator tag support for Dictionary and HashSet

Source/Engine/Core/Collections/Dictionary.h

@@ -163,6 +163,15 @@ public:
     {
     }
 
+    /// <summary>
+    /// Initializes an empty <see cref="Dictionary"/> without reserving any space.
+    /// </summary>
+    /// <param name="tag">The custom allocation tag.</param>
+    Dictionary(typename Base::AllocationTag tag)
+        : Base(tag)
+    {
+    }
+
     /// <summary>
     /// Initializes <see cref="Dictionary"/> by reserving space.
     /// </summary>

Source/Engine/Core/Collections/HashSet.h

@@ -140,6 +140,15 @@ public:
     {
     }
 
+    /// <summary>
+    /// Initializes an empty <see cref="HashSet"/> without reserving any space.
+    /// </summary>
+    /// <param name="tag">The custom allocation tag.</param>
+    HashSet(typename Base::AllocationTag tag)
+        : Base(tag)
+    {
+    }
+
     /// <summary>
     /// Initializes <see cref="HashSet"/> by reserving space.
     /// </summary>

Source/Engine/Core/Collections/HashSetBase.h

@@ -59,6 +59,7 @@ class HashSetBase
 public:
     // Type of allocation data used to store hash set buckets.
     using AllocationData = typename AllocationType::template Data<BucketType>;
+    using AllocationTag = typename AllocationType::Tag;
 
 protected:
     int32 _elementsCount = 0;
@@ -70,6 +71,11 @@ protected:
     {
     }
 
+    HashSetBase(AllocationTag tag)
+        : _allocation(tag)
+    {
+    }
+
     void MoveToEmpty(HashSetBase&& other)
     {
         _elementsCount = other._elementsCount;

Source/Engine/Core/Memory/ArenaAllocation.h

@@ -138,7 +138,7 @@ public:
         FORCE_INLINE void Swap(Data& other)
         {
             ::Swap(_data, other._data);
-            ::Swap(_arena, other._arena);
+            _arena = other._arena; // TODO: find a better way to move allocation with AllocationUtils::MoveToEmpty to preserve/maintain allocation tag ownership
         }
     };
 };