EDK: Move ref counting classes to mojo/edk/util.

mojo/edk/system/channel_endpoint_unittest.cc

Index: mojo/edk/system/channel_endpoint_unittest.cc
diff --git a/mojo/edk/system/channel_endpoint_unittest.cc b/mojo/edk/system/channel_endpoint_unittest.cc
index 6aa1ef61cf6d684d9770bbc1d4dadc6d04e379f8..5c93fb2534748ed3a24e6c842322b83d711f153c 100644
--- a/mojo/edk/system/channel_endpoint_unittest.cc
+++ b/mojo/edk/system/channel_endpoint_unittest.cc
@@ -10,12 +10,14 @@
 #include "mojo/edk/system/channel_test_base.h"
 #include "mojo/edk/system/message_in_transit_queue.h"
 #include "mojo/edk/system/message_in_transit_test_utils.h"
-#include "mojo/edk/system/ref_ptr.h"
 #include "mojo/edk/system/test/timeouts.h"
 #include "mojo/edk/system/test_channel_endpoint_client.h"
 #include "mojo/edk/system/waitable_event.h"
+#include "mojo/edk/util/ref_ptr.h"
 #include "mojo/public/cpp/system/macros.h"
 
+using mojo::util::MakeRefCounted;
+
 namespace mojo {
 namespace system {
 namespace {