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/compiler/utils/arm64/assembler_arm64.h b/compiler/utils/arm64/assembler_arm64.h
index 0f4a9a4..ab4999a 100644
--- a/compiler/utils/arm64/assembler_arm64.h
+++ b/compiler/utils/arm64/assembler_arm64.h
@@ -17,8 +17,9 @@
 #ifndef ART_COMPILER_UTILS_ARM64_ASSEMBLER_ARM64_H_
 #define ART_COMPILER_UTILS_ARM64_ASSEMBLER_ARM64_H_
 
-#include <vector>
 #include <stdint.h>
+#include <memory>
+#include <vector>
 
 #include "base/logging.h"
 #include "constants_arm64.h"
@@ -26,7 +27,6 @@
 #include "utils/assembler.h"
 #include "offsets.h"
 #include "utils.h"
-#include "UniquePtrCompat.h"
 #include "a64/macro-assembler-a64.h"
 #include "a64/disasm-a64.h"