TaskManager: use an unordered_map for tracking network usage

chrome/browser/task_manager/sampling/task_manager_impl.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_MANAGER_SAMPLING_TASK_MANAGER_IMPL_H_
 #define CHROME_BROWSER_TASK_MANAGER_SAMPLING_TASK_MANAGER_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 81 matching lines @@
       content::WebContents* web_contents) const override;
 
   // task_manager::TaskProviderObserver:
   void TaskAdded(Task* task) override;
   void TaskRemoved(Task* task) override;
   void TaskUnresponsive(Task* task) override;
 
   // The notification method on the UI thread when multiple bytes are
   // transferred from URLRequests. This will be called by the
   // |io_thread_helper_|
-  static void OnMultipleBytesTransferredUI(
-      std::vector<BytesTransferredParam>* params);
+  static void OnMultipleBytesTransferredUI(BytesTransferredMap params);
 
  private:
   friend struct base::LazyInstanceTraitsBase<TaskManagerImpl>;
 
   TaskManagerImpl();
 
   void OnVideoMemoryUsageStatsUpdate(
       const gpu::VideoMemoryUsageStats& gpu_memory_stats);
 
   // task_manager::TaskManagerInterface:
   void Refresh() override;
   void StartUpdating() override;
   void StopUpdating() override;
 
   // Lookup a task by its pid, child_id and possibly route_id.
   Task* GetTaskByPidOrRoute(int pid, int child_id, int route_id) const;
 
   // Based on |param| the appropriate task will be updated by its network usage.
   // Returns true if it was able to match |param| to an existing task, returns
   // false otherwise, at which point the caller must explicitly match these
   // bytes to the browser process by calling this method again with
   // |param.origin_pid = 0| and |param.child_id = param.route_id = -1|.
-  bool UpdateTasksWithBytesTransferred(const BytesTransferredParam& param);
+  bool UpdateTasksWithBytesTransferred(const BytesTransferredKey& key,
+                                       const BytesTransferredParam& param);
 
   TaskGroup* GetTaskGroupByTaskId(TaskId task_id) const;
   Task* GetTaskByTaskId(TaskId task_id) const;
 
   // Called back by a TaskGroup when the resource calculations done on the
   // background thread has completed.
   void OnTaskGroupBackgroundCalculationsDone();
 
   const base::Closure on_background_data_ready_callback_;
 
@@ skipping 33 matching lines @@
   // running.
   bool is_running_;
 
   base::WeakPtrFactory<TaskManagerImpl> weak_ptr_factory_;
   DISALLOW_COPY_AND_ASSIGN(TaskManagerImpl);
 };
 
 }  // namespace task_manager
 
 #endif  // CHROME_BROWSER_TASK_MANAGER_SAMPLING_TASK_MANAGER_IMPL_H_