Rewrite base::Bind into base::BindOnce on trivial cases in base

base/threading/thread.cc

Index: base/threading/thread.cc
diff --git a/base/threading/thread.cc b/base/threading/thread.cc
index 0aeed2a9e4b5ac2c2a5e7bac1929e881b827361c..75c911b7f87dced1d2b9695a86af4f8efc2f1aff 100644
--- a/base/threading/thread.cc
+++ b/base/threading/thread.cc
@@ -156,7 +156,7 @@ void Thread::FlushForTesting() {
   WaitableEvent done(WaitableEvent::ResetPolicy::AUTOMATIC,
                      WaitableEvent::InitialState::NOT_SIGNALED);
   task_runner()->PostTask(FROM_HERE,
-                          Bind(&WaitableEvent::Signal, Unretained(&done)));
+                          BindOnce(&WaitableEvent::Signal, Unretained(&done)));
   done.Wait();
 }
 
@@ -210,7 +210,7 @@ void Thread::StopSoon() {
   }
 
   task_runner()->PostTask(
-      FROM_HERE, base::Bind(&Thread::ThreadQuitHelper, Unretained(this)));
+      FROM_HERE, base::BindOnce(&Thread::ThreadQuitHelper, Unretained(this)));
 }
 
 void Thread::DetachFromSequence() {