ART: Update stl_util.h

Replace MakeUnique with std::make_unique. Remove unused functions.

Test: m
Change-Id: I3afdc0529cd6fb9d1797e5294a3d5ea2f6b38fc7
diff --git a/compiler/oat_test.cc b/compiler/oat_test.cc
index 84ec8b3..55d0bd9 100644
--- a/compiler/oat_test.cc
+++ b/compiler/oat_test.cc
@@ -225,8 +225,8 @@
                                       oat_writer.GetBssRootsOffset());
 
     if (kIsVdexEnabled) {
-      std::unique_ptr<BufferedOutputStream> vdex_out(
-            MakeUnique<BufferedOutputStream>(MakeUnique<FileOutputStream>(vdex_file)));
+      std::unique_ptr<BufferedOutputStream> vdex_out =
+            std::make_unique<BufferedOutputStream>(std::make_unique<FileOutputStream>(vdex_file));
       if (!oat_writer.WriteVerifierDeps(vdex_out.get(), nullptr)) {
         return false;
       }