New cpp folder structure

Signed-off-by: Alexander Borsuk <me@alex.bio>

libs/search/feature_loader.hpp

@@ -0,0 +1,39 @@
+#pragma once
+
+#include "indexer/data_source.hpp"
+#include "indexer/scales.hpp"
+
+#include "base/assert.hpp"
+#include "base/macros.hpp"
+#include "base/thread_checker.hpp"
+
+#include <memory>
+#include <utility>
+
+class FeatureType;
+struct FeatureID;
+
+namespace search
+{
+class FeatureLoader
+{
+public:
+  explicit FeatureLoader(DataSource const & dataSource);
+
+  std::unique_ptr<FeatureType> Load(FeatureID const & id);
+
+  void Reset();
+
+  void ForEachInRect(m2::RectD const & rect, std::function<void(FeatureType &)> const & fn)
+  {
+    ASSERT(m_checker.CalledOnOriginalThread(), ());
+    m_dataSource.ForEachInRect(fn, rect, scales::GetUpperScale());
+  }
+
+private:
+  DataSource const & m_dataSource;
+  std::unique_ptr<FeaturesLoaderGuard> m_guard;
+
+  ThreadChecker m_checker;
+};
+}  // namespace search