Replace std::tr1::shared_ptr by std::shared_ptr.

This patch replaces C++ Technical Report 1 additions to C++03 with
the newer C++11 name.

Includes and using statements updated accordingly.

BUG=None
TEST=Build and unittests.

Change-Id: I9bdad6d39684545c786f5c76fb598a15b557d6eb
Reviewed-on: https://chromium-review.googlesource.com/200665
Tested-by: Alex Deymo <deymo@chromium.org>
Reviewed-by: David Zeuthen <zeuthen@chromium.org>
Commit-Queue: Alex Deymo <deymo@chromium.org>
diff --git a/update_attempter.h b/update_attempter.h
index 9c460ad..82cba8c 100644
--- a/update_attempter.h
+++ b/update_attempter.h
@@ -7,7 +7,7 @@
 
 #include <time.h>
 
-#include <tr1/memory>
+#include <memory>
 #include <string>
 #include <vector>
 
@@ -354,7 +354,7 @@
   // set back in the middle of an update.
   base::TimeTicks last_notify_time_;
 
-  std::vector<std::tr1::shared_ptr<AbstractAction> > actions_;
+  std::vector<std::shared_ptr<AbstractAction> > actions_;
   scoped_ptr<ActionProcessor> processor_;
 
   // External state of the system outside the update_engine process
@@ -366,10 +366,10 @@
   UpdateEngineService* dbus_service_ = nullptr;
 
   // Pointer to the OmahaResponseHandlerAction in the actions_ vector.
-  std::tr1::shared_ptr<OmahaResponseHandlerAction> response_handler_action_;
+  std::shared_ptr<OmahaResponseHandlerAction> response_handler_action_;
 
   // Pointer to the DownloadAction in the actions_ vector.
-  std::tr1::shared_ptr<DownloadAction> download_action_;
+  std::shared_ptr<DownloadAction> download_action_;
 
   // Pointer to the preferences store interface. This is just a cached
   // copy of system_state->prefs() because it's used in many methods and