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/Android.mk b/compiler/Android.mk
index 8592aaa..cb900ea 100644
--- a/compiler/Android.mk
+++ b/compiler/Android.mk
@@ -170,7 +170,6 @@
   ifeq ($$(art_target_or_host),host)
     LOCAL_IS_HOST_MODULE := true
   endif
-  include art/build/Android.libcxx.mk
   LOCAL_CPP_EXTENSION := $(ART_CPP_EXTENSION)
   ifeq ($$(art_ndebug_or_debug),ndebug)
     LOCAL_MODULE := libart-compiler
@@ -196,6 +195,7 @@
 
   LOCAL_CFLAGS := $$(LIBART_COMPILER_CFLAGS)
   ifeq ($$(art_target_or_host),target)
+    include external/libcxx/libcxx.mk
     LOCAL_CLANG := $(ART_TARGET_CLANG)
     LOCAL_CFLAGS += $(ART_TARGET_CFLAGS)
   else # host