Remove task.h and finish base::Bind() migration.

base/task.h

Index: base/task.h
diff --git a/base/task.h b/base/task.h
deleted file mode 100644
index dbef70be032350c3f552ac41e7db69ef80939634..0000000000000000000000000000000000000000
--- a/base/task.h
+++ /dev/null
@@ -1,69 +0,0 @@
-// 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.
-
-// ============================================================================
-// ****************************************************************************
-// *  THIS HEADER IS DEPRECATED, SEE base/callback.h FOR NEW IMPLEMENTATION   *
-// ****************************************************************************
-// ============================================================================
-// ============================================================================
-// ****************************************************************************
-// *  THIS HEADER IS DEPRECATED, SEE base/callback.h FOR NEW IMPLEMENTATION   *
-// ****************************************************************************
-// ============================================================================
-// ============================================================================
-// ****************************************************************************
-// *  THIS HEADER IS DEPRECATED, SEE base/callback.h FOR NEW IMPLEMENTATION   *
-// ****************************************************************************
-// ============================================================================
-// ============================================================================
-// ****************************************************************************
-// *  THIS HEADER IS DEPRECATED, SEE base/callback.h FOR NEW IMPLEMENTATION   *
-// ****************************************************************************
-// ============================================================================
-// ============================================================================
-// ****************************************************************************
-// *  THIS HEADER IS DEPRECATED, SEE base/callback.h FOR NEW IMPLEMENTATION   *
-// ****************************************************************************
-// ============================================================================
-#ifndef BASE_TASK_H_
-#define BASE_TASK_H_
-#pragma once
-
-#include "base/base_export.h"
-#include "base/callback.h"
-#include "base/debug/alias.h"
-#include "base/memory/raw_scoped_refptr_mismatch_checker.h"
-#include "base/memory/weak_ptr.h"
-#include "base/tuple.h"
-
-namespace base {
-const size_t kDeadTask = 0xDEAD7A53;
-}
-
-template<typename T>
-void DeletePointer(T* obj) {
-  delete obj;
-}
-
-namespace base {
-
-// ScopedClosureRunner is akin to scoped_ptr for Closures. It ensures that the
-// Closure is executed and deleted no matter how the current scope exits.
-class BASE_EXPORT ScopedClosureRunner {
- public:
-  explicit ScopedClosureRunner(const Closure& closure);
-  ~ScopedClosureRunner();
-
-  Closure Release();
-
- private:
-  Closure closure_;
-
-  DISALLOW_IMPLICIT_CONSTRUCTORS(ScopedClosureRunner);
-};
-
-}  // namespace base
-
-#endif  // BASE_TASK_H_