Add missing (and remove superfluous) 'explicit' from constructors.

base/task_runner.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/task_runner.h"
 
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/threading/post_task_and_reply_impl.h"
 
 namespace base {
 
 namespace {
 
 // TODO(akalin): There's only one other implementation of
 // PostTaskAndReplyImpl in WorkerPool.  Investigate whether it'll be
 // possible to merge the two.
 class PostTaskAndReplyTaskRunner : public internal::PostTaskAndReplyImpl {
  public:
-  PostTaskAndReplyTaskRunner(TaskRunner* destination);
+  explicit PostTaskAndReplyTaskRunner(TaskRunner* destination);
 
  private:
   virtual bool PostTask(const tracked_objects::Location& from_here,
                         const Closure& task) OVERRIDE;
 
   // Non-owning.
   TaskRunner* destination_;
 };
 
 PostTaskAndReplyTaskRunner::PostTaskAndReplyTaskRunner(
@@ skipping 28 matching lines @@
 
 void TaskRunner::OnDestruct() const {
   delete this;
 }
 
 void TaskRunnerTraits::Destruct(const TaskRunner* task_runner) {
   task_runner->OnDestruct();
 }
 
 }  // namespace base