Make PendingTask move-only and pass it by value on retaining params

base/message_loop/message_loop.h

Index: base/message_loop/message_loop.h
diff --git a/base/message_loop/message_loop.h b/base/message_loop/message_loop.h
index 1230f4196d0799c5ed59fe4a51e320de2eb6bf88..761c18cafebca857f4541a8d93db249e01bb1d61 100644
--- a/base/message_loop/message_loop.h
+++ b/base/message_loop/message_loop.h
@@ -450,10 +450,10 @@ class BASE_EXPORT MessageLoop : public MessagePump::Delegate {
 
   // Calls RunTask or queues the pending_task on the deferred task list if it
   // cannot be run right now.  Returns true if the task was run.
-  bool DeferOrRunPendingTask(const PendingTask& pending_task);
+  bool DeferOrRunPendingTask(PendingTask pending_task);
 
   // Adds the pending task to delayed_work_queue_.
-  void AddToDelayedWorkQueue(const PendingTask& pending_task);
+  void AddToDelayedWorkQueue(PendingTask pending_task);
 
   // Delete tasks that haven't run yet without running them.  Used in the
   // destructor to make sure all the task's destructors get called.  Returns