Use std::default_delete as the default deleter for scoped_ptr.

The aim is to make scoped_ptr and std::unique_ptr functionally
identical so scoped_ptr can simply be a typedef.

BUG=554298

Review URL: https://codereview.chromium.org/1445003002

Cr-Commit-Position: refs/heads/master@{#360539}
diff --git a/ipc/mojo/ipc_channel_mojo.cc b/ipc/mojo/ipc_channel_mojo.cc
index 8ae0de50..97330dc 100644
--- a/ipc/mojo/ipc_channel_mojo.cc
+++ b/ipc/mojo/ipc_channel_mojo.cc
@@ -4,6 +4,8 @@
 
 #include "ipc/mojo/ipc_channel_mojo.h"
 
+#include <memory>
+
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
@@ -361,7 +363,7 @@
 // ClosingDeleter calls |CloseWithErrorIfPending| before deleting the
 // |MessagePipeReader|.
 struct ClosingDeleter {
-  typedef base::DefaultDeleter<internal::MessagePipeReader> DefaultType;
+  typedef std::default_delete<internal::MessagePipeReader> DefaultType;
 
   void operator()(internal::MessagePipeReader* ptr) const {
     ptr->CloseWithErrorIfPending();