Now we have a proper C++ library, use std::unique_ptr.

Also remove the Android.libcxx.mk and other bits of stlport compatibility
mechanics.

Change-Id: Icdf7188ba3c79cdf5617672c1cfd0a68ae596a61
diff --git a/runtime/safe_map.h b/runtime/safe_map.h
index 393bf92..190db60 100644
--- a/runtime/safe_map.h
+++ b/runtime/safe_map.h
@@ -27,7 +27,7 @@
 // Equivalent to std::map, but without operator[] and its bug-prone semantics (in particular,
 // the implicit insertion of a default-constructed value on failed lookups).
 template <typename K, typename V, typename Comparator = std::less<K>,
-          typename Allocator = std::allocator<std::pair<const K, V> > >
+          typename Allocator = std::allocator<std::pair<const K, V>>>
 class SafeMap {
  private:
   typedef SafeMap<K, V, Comparator, Allocator> Self;