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/p2p_manager.cc b/p2p_manager.cc
index 2ec827a..b1383e2 100644
--- a/p2p_manager.cc
+++ b/p2p_manager.cc
@@ -25,6 +25,7 @@
 
 #include <algorithm>
 #include <map>
+#include <memory>
 #include <utility>
 #include <vector>
 
@@ -42,6 +43,7 @@
 using std::map;
 using std::pair;
 using std::string;
+using std::unique_ptr;
 using std::vector;
 
 namespace chromeos_update_engine {
@@ -139,7 +141,7 @@
   const policy::DevicePolicy* device_policy_;
 
   // Configuration object.
-  scoped_ptr<Configuration> configuration_;
+  unique_ptr<Configuration> configuration_;
 
   // Object for persisted state.
   PrefsInterface* prefs_;
@@ -235,7 +237,7 @@
   gint exit_status = 0;
 
   vector<string> args = configuration_->GetInitctlArgs(should_be_running);
-  scoped_ptr<gchar*, GLibStrvFreeDeleter> argv(
+  unique_ptr<gchar*, GLibStrvFreeDeleter> argv(
       utils::StringVectorToGStrv(args));
   if (!g_spawn_sync(nullptr,  // working_directory
                     argv.get(),
@@ -250,7 +252,7 @@
                << ": " << utils::GetAndFreeGError(&error);
     return false;
   }
-  scoped_ptr<gchar, GLibFreeDeleter> standard_error_deleter(standard_error);
+  unique_ptr<gchar, GLibFreeDeleter> standard_error_deleter(standard_error);
 
   if (!WIFEXITED(exit_status)) {
     LOG(ERROR) << "Error spawning '" << utils::StringVectorToString(args)