Fix TaskmanagerIoThreadHelper bug.

chrome/browser/task_management/sampling/task_manager_io_thread_helper.h

 // Copyright 2015 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.
 
 #ifndef CHROME_BROWSER_TASK_MANAGEMENT_SAMPLING_TASK_MANAGER_IO_THREAD_HELPER_H_
 #define CHROME_BROWSER_TASK_MANAGEMENT_SAMPLING_TASK_MANAGER_IO_THREAD_HELPER_H_
 
 #include <stdint.h>
 
 #include <vector>
 
 #include "base/macros.h"
+#include "base/memory/weak_ptr.h"
 
 namespace net {
 class URLRequest;
 }  // namespace net
 
 namespace task_management {
 
 // Defines a wrapper of values that will be sent from IO to UI thread upon
 // reception of bytes read notifications.
 struct BytesReadParam {
@@ skipping 48 matching lines @@
   // TaskManagerInterface if the new task manager is enabled.
   static void OnRawBytesRead(const net::URLRequest& request,
                              int64_t bytes_read);
 
  private:
   TaskManagerIoThreadHelper();
   ~TaskManagerIoThreadHelper();
 
   // We gather multiple notifications on the IO thread in one second before a
   // call is made to the following function to start the processing.
-  static void OnMultipleBytesReadIO();
+  void OnMultipleBytesReadIO();
 
   // This will update the task manager with the network bytes read.
   void OnNetworkBytesRead(const net::URLRequest& request, int64_t bytes_read);
 
   // This buffer will be filled on IO thread with information about the number
   // of bytes read from URLRequests.
   std::vector<BytesReadParam> bytes_read_buffer_;
 
+  base::WeakPtrFactory<TaskManagerIoThreadHelper> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(TaskManagerIoThreadHelper);
 };
 
 }  // namespace task_management
 
 #endif  // CHROME_BROWSER_TASK_MANAGEMENT_SAMPLING_TASK_MANAGER_IO_THREAD_HELPER_H_