Convert //sandbox to use std::unique_ptr

sandbox/win/src/process_policy_test.cc

Index: sandbox/win/src/process_policy_test.cc
diff --git a/sandbox/win/src/process_policy_test.cc b/sandbox/win/src/process_policy_test.cc
index 587678135276c4c7f59e6c61fc3660cb01a80d52..2794595cb319eb362654fc69200c4c433235e323 100644
--- a/sandbox/win/src/process_policy_test.cc
+++ b/sandbox/win/src/process_policy_test.cc
@@ -6,7 +6,6 @@
 #include <string>
 
 #include "base/memory/free_deleter.h"
-#include "base/memory/scoped_ptr.h"
 #include "base/strings/string16.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/win/scoped_handle.h"
@@ -31,7 +30,7 @@ sandbox::SboxTestResult CreateProcessHelper(const base::string16& exe,
   if (!exe.empty())
     exe_name = exe.c_str();
 
-  scoped_ptr<wchar_t, base::FreeDeleter>  writable_command(
+  std::unique_ptr<wchar_t, base::FreeDeleter> writable_command(
       _wcsdup(command.c_str()));
 
   // Create the process with the unicode version of the API.