Fixed JSON StatsString printed from VirtualBlock

Fix in VirtualBlock::BuildStatsString.
diff --git a/src/D3D12MemAlloc.cpp b/src/D3D12MemAlloc.cpp
index f49bdca..cfb8463 100644
--- a/src/D3D12MemAlloc.cpp
+++ b/src/D3D12MemAlloc.cpp
@@ -10272,11 +10272,13 @@
 

     D3D12MA_DEBUG_GLOBAL_MUTEX_LOCK

 

-        StringBuilder sb(m_Pimpl->m_AllocationCallbacks);

+    StringBuilder sb(m_Pimpl->m_AllocationCallbacks);

     {

         JsonWriter json(m_Pimpl->m_AllocationCallbacks, sb);

         D3D12MA_HEAVY_ASSERT(m_Pimpl->m_Metadata->Validate());

+        json.BeginObject();

         m_Pimpl->m_Metadata->WriteAllocationInfoToJson(json);

+        json.EndObject();

     } // Scope for JsonWriter

 

     const size_t length = sb.GetLength();