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/download_action.h b/download_action.h
index e53ee34..8e3809a 100644
--- a/download_action.h
+++ b/download_action.h
@@ -9,9 +9,9 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 
+#include <memory>
 #include <string>
 
-#include <base/memory/scoped_ptr.h>
 #include <curl/curl.h>
 
 #include "update_engine/action.h"
@@ -113,13 +113,13 @@
   SystemState* system_state_;
 
   // Pointer to the HttpFetcher that does the http work.
-  scoped_ptr<HttpFetcher> http_fetcher_;
+  std::unique_ptr<HttpFetcher> http_fetcher_;
 
   // The FileWriter that downloaded data should be written to. It will
   // either point to *decompressing_file_writer_ or *delta_performer_.
   FileWriter* writer_;
 
-  scoped_ptr<DeltaPerformer> delta_performer_;
+  std::unique_ptr<DeltaPerformer> delta_performer_;
 
   // Used by TransferTerminated to figure if this action terminated itself or
   // was terminated by the action processor.