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

base/observer_list_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/observer_list.h"
 #include "base/observer_list_threadsafe.h"
 
 #include <utility>
 #include <vector>
 
@@ skipping 100 matching lines @@
         do_notifies_(notify),
         weak_factory_(this) {
   }
 
   ~AddRemoveThread() override {}
 
   void ThreadMain() override {
     loop_ = new MessageLoop();  // Fire up a message loop.
     loop_->task_runner()->PostTask(
         FROM_HERE,
-        base::Bind(&AddRemoveThread::AddTask, weak_factory_.GetWeakPtr()));
+        base::BindOnce(&AddRemoveThread::AddTask, weak_factory_.GetWeakPtr()));
     RunLoop().Run();
     delete loop_;
     loop_ = reinterpret_cast<MessageLoop*>(0xdeadbeef);
     delete this;
   }
 
   // This task just keeps posting to itself in an attempt
   // to race with the notifier.
   void AddTask() {
     count_addtask_++;
 
     if ((Time::Now() - start_).InMilliseconds() > kThreadRunTime) {
       VLOG(1) << "DONE!";
       return;
     }
 
     if (!in_list_) {
       list_->AddObserver(this);
       in_list_ = true;
     }
 
     if (do_notifies_) {
       list_->Notify(FROM_HERE, &Foo::Observe, 10);
     }
 
     loop_->task_runner()->PostTask(
         FROM_HERE,
-        base::Bind(&AddRemoveThread::AddTask, weak_factory_.GetWeakPtr()));
+        base::BindOnce(&AddRemoveThread::AddTask, weak_factory_.GetWeakPtr()));
   }
 
   void Quit() {
     loop_->task_runner()->PostTask(FROM_HERE,
                                    MessageLoop::QuitWhenIdleClosure());
   }
 
   void Observe(int x) override {
     count_observes_++;
 
@@ skipping 888 matching lines @@
     // However, the first Observe() call will add a second observer: at this
     // point, it != observer_list.end() should be true, and Observe() should be
     // called on the newly added observer on the next iteration of the loop.
     observer.Observe(10);
   }
 
   EXPECT_EQ(-10, b.total);
 }
 
 }  // namespace base