Less unneeded generality in sorted-vector ctors

Summary: [Folly] Less unneeded generality in `sorted_vector_set` and `sorted_vector_map` ctors in terms of `begin` and `end` - can just use member functions.

Reviewed By: vitaut

Differential Revision: D15215590

fbshipit-source-id: e6c8c92fdd9ae16963768b4f748aa07e9566f947

folly/sorted_vector_types.h

@@ -197,8 +197,7 @@ void bulk_insert(
 
 template <typename Container, typename Compare>
 Container&& as_sorted(Container&& container, Compare const& comp) {
-  using namespace std;
-  std::sort(begin(container), end(container), comp);
+  std::sort(container.begin(), container.end(), comp);
   return static_cast<Container&&>(container);
 }
 } // namespace detail