update_engine: Replace scoped_ptr with std::unique_ptr.

BUG=None
TEST=`FEATURES=test emerge-$BOARD update_engine`
TEST=`USE='clang asan' FEATURES=test emerge-$BOARD update_engine`

Change-Id: I55a2f7f53675faaac20ba25f72ed52cf938d7744
Reviewed-on: https://chromium-review.googlesource.com/224189
Tested-by: Ben Chan <benchan@chromium.org>
Reviewed-by: Alex Deymo <deymo@chromium.org>
Commit-Queue: Ben Chan <benchan@chromium.org>
diff --git a/update_manager/update_manager-inl.h b/update_manager/update_manager-inl.h
index a9f051f..5e30031 100644
--- a/update_manager/update_manager-inl.h
+++ b/update_manager/update_manager-inl.h
@@ -5,6 +5,7 @@
 #ifndef UPDATE_ENGINE_UPDATE_MANAGER_UPDATE_MANAGER_INL_H_
 #define UPDATE_ENGINE_UPDATE_MANAGER_UPDATE_MANAGER_INL_H_
 
+#include <memory>
 #include <string>
 
 #include <base/bind.h>
@@ -129,7 +130,7 @@
   scoped_refptr<EvaluationContext> ec =
       new EvaluationContext(
           clock_, evaluation_timeout_, expiration_timeout_,
-          scoped_ptr<base::Callback<void(EvaluationContext*)>>(
+          std::unique_ptr<base::Callback<void(EvaluationContext*)>>(
               new base::Callback<void(EvaluationContext*)>(
                   base::Bind(&UpdateManager::UnregisterEvalContext,
                              weak_ptr_factory_.GetWeakPtr()))));