TaskManager: when shown or activated, select the last active tab.

chrome/browser/task_management/task_manager_interface.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_TASK_MANAGER_INTERFACE_H_
 #define CHROME_BROWSER_TASK_MANAGEMENT_TASK_MANAGER_INTERFACE_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
 #include <utility>
 
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "base/process/kill.h"
 #include "base/process/process_handle.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
 #include "chrome/browser/task_management/providers/task.h"
 #include "chrome/browser/task_management/task_manager_observer.h"
 #include "third_party/WebKit/public/web/WebCache.h"
 #include "ui/gfx/image/image_skia.h"
 
 class PrefRegistrySimple;
 
+namespace content {
+class WebContents;
+}  // namespace content
+
 namespace net {
 class URLRequest;
 }  // namespace net
 
 namespace task_management {
 
 // Defines the interface for any implementation of the task manager.
 // Concrete implementations have no control over the refresh rate nor the
 // enabled calculations of the usage of the various resources.
 class TaskManagerInterface {
@@ skipping 161 matching lines @@
   virtual const TaskIdList& GetTaskIdsList() const = 0;
 
   // Gets the list of task IDs of the tasks that run on the same process as the
   // task with |task_id|. The returned list will at least include |task_id|.
   virtual TaskIdList GetIdsOfTasksSharingSameProcess(TaskId task_id) const = 0;
 
   // Gets the number of task-manager tasks running on the same process on which
   // the Task with |task_id| is running.
   virtual size_t GetNumberOfTasksOnSameProcess(TaskId task_id) const = 0;
 
+  // Returns the TaskId associated with the main task for |web_contents|.
+  // Returns -1 if |web_contents| is nullptr or does not currently have an
+  // associated Task.
+  virtual TaskId GetTaskIdForWebContents(
+      content::WebContents* web_contents) const = 0;
+
   // Returns true if the resource |type| usage calculation is enabled and
   // the implementation should refresh its value (this means that at least one
   // of the observers require this value). False otherwise.
   bool IsResourceRefreshEnabled(RefreshType type) const;
 
  protected:
   TaskManagerInterface();
   virtual ~TaskManagerInterface();
 
   // Notifying observers of various events.
@@ skipping 47 matching lines @@
 
   // The flags containing the enabled resources types calculations.
   int64_t enabled_resources_flags_;
 
   DISALLOW_COPY_AND_ASSIGN(TaskManagerInterface);
 };
 
 }  // namespace task_management
 
 #endif  // CHROME_BROWSER_TASK_MANAGEMENT_TASK_MANAGER_INTERFACE_H_