Convert mojo::system::Dispatcher to use our new refcounting stuff (instead of base's).

mojo/edk/system/waiter_test_utils.h

Index: mojo/edk/system/waiter_test_utils.h
diff --git a/mojo/edk/system/waiter_test_utils.h b/mojo/edk/system/waiter_test_utils.h
index ee2f68c721f9b823d198c8f6108ad625f77caeb1..b45ba09fa255dd7eebad1ed6e6a26a7d6a2c624e 100644
--- a/mojo/edk/system/waiter_test_utils.h
+++ b/mojo/edk/system/waiter_test_utils.h
@@ -7,9 +7,9 @@
 
 #include <stdint.h>
 
-#include "base/memory/ref_counted.h"
 #include "mojo/edk/system/dispatcher.h"
 #include "mojo/edk/system/handle_signals_state.h"
+#include "mojo/edk/system/ref_ptr.h"
 #include "mojo/edk/system/waiter.h"
 #include "mojo/edk/test/simple_test_thread.h"
 #include "mojo/public/c/system/types.h"
@@ -70,7 +70,7 @@ class WaiterThread : public mojo::test::SimpleTestThread {
   // Note: |*did_wait_out|, |*result_out|, |*context_out| and
   // |*signals_state_out| "belong" to this object (i.e., may be modified by, on
   // some other thread) while it's alive.
-  WaiterThread(scoped_refptr<Dispatcher> dispatcher,
+  WaiterThread(RefPtr<Dispatcher>&& dispatcher,
                MojoHandleSignals handle_signals,
                MojoDeadline deadline,
                uint32_t context,
@@ -83,7 +83,7 @@ class WaiterThread : public mojo::test::SimpleTestThread {
  private:
   void Run() override;
 
-  const scoped_refptr<Dispatcher> dispatcher_;
+  const RefPtr<Dispatcher> dispatcher_;
   const MojoHandleSignals handle_signals_;
   const MojoDeadline deadline_;
   const uint32_t context_;