nullvideo: initial release of null video backend

Source/Core/VideoBackends/Null/PerfQuery.h

@@ -0,0 +1,24 @@
+// Copyright 2015 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "VideoCommon/PerfQueryBase.h"
+
+namespace Null
+{
+class PerfQuery : public PerfQueryBase
+{
+public:
+  PerfQuery() {}
+  ~PerfQuery() override {}
+  void EnableQuery(PerfQueryGroup type) override {}
+  void DisableQuery(PerfQueryGroup type) override {}
+  void ResetQuery() override {}
+  u32 GetQueryResult(PerfQueryType type) override { return 0; }
+  void FlushResults() override {}
+  bool IsFlushed() const { return true; }
+};
+
+}  // namespace