Notify DataUseTabModel of navigations and tab closures

chrome/browser/android/data_usage/data_use_tab_model.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_ANDROID_DATA_USAGE_DATA_USE_TAB_MODEL_H_
 #define CHROME_BROWSER_ANDROID_DATA_USAGE_DATA_USE_TAB_MODEL_H_
 
 #include <stdint.h>
 
 #include <string>
 
 #include "base/containers/hash_tables.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
-#include "base/observer_list_threadsafe.h"
+#include "base/observer_list.h"
 #include "base/threading/thread_checker.h"
 #include "chrome/browser/android/data_usage/tab_data_use_entry.h"
 #include "components/data_usage/core/data_use.h"
 #include "url/gurl.h"
 
 namespace chrome {
 
 namespace android {
 
 class ExternalDataUseObserver;
@@ skipping 48 matching lines @@
 
   DataUseTabModel(const ExternalDataUseObserver* data_use_observer,
                   scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner);
 
   ~DataUseTabModel();
 
   base::WeakPtr<DataUseTabModel> GetWeakPtr();
 
   // Notifies the DataUseTabModel of navigation events. |tab_id| is the source
   // tab of the generated event, |transition| indicates the type of the UI
-  // event/transition,  |url| is the URL in the source tab, |package| indicates
-  // the android package name of external application that initiated the event.
+  // event/transition,  |url| is the URL in the source tab.
   void OnNavigationEvent(int32_t tab_id,
                          TransitionType transition,
-                         const GURL& url,
-                         const std::string& package);
+                         const GURL& url);
 
   // Notifies the DataUseTabModel that tab with |tab_id| is closed. Any active
   // tracking sessions for the tab are terminated, and the tab is marked as
   // closed.
   void OnTabCloseEvent(int32_t tab_id);
 
   // Gets the label for the |data_use| object. |output_label| must not be null.
   // If a tab tracking session is found that was active at the time of request
   // start of |data_use|, returns true and |output_label| is populated with its
   // label. Otherwise returns false and |output_label| is set to empty string.
   bool GetLabelForDataUse(const data_usage::DataUse& data_use,
                           std::string* output_label) const;
 
-  // Adds or removes observers from the observer list. These functions are
-  // thread-safe and can be called from any thread.
+  // Adds or removes observers from the observer list. Must be called only on
+  // IO thread.
   void AddObserver(TabDataUseObserver* observer);
   void RemoveObserver(TabDataUseObserver* observer);
 
+ protected:
+  // Notifies the observers that a data usage tracking session started for
+  // |tab_id|. Protected for testing.
+  void NotifyObserversOfTrackingStarting(int32_t tab_id);
+
+  // Notifies the observers that an active data usage tracking session ended for
+  // |tab_id|. Protected for testing.
+  void NotifyObserversOfTrackingEnding(int32_t tab_id);
+
  private:
   friend class DataUseTabModelTest;
   friend class MockTabDataUseEntryTest;
   FRIEND_TEST_ALL_PREFIXES(DataUseTabModelTest, SingleTabTracking);
   FRIEND_TEST_ALL_PREFIXES(DataUseTabModelTest, MultipleTabTracking);
   FRIEND_TEST_ALL_PREFIXES(DataUseTabModelTest, ObserverStartEndEvents);
   FRIEND_TEST_ALL_PREFIXES(DataUseTabModelTest, ObserverNotNotifiedAfterRemove);
   FRIEND_TEST_ALL_PREFIXES(DataUseTabModelTest,
                            MultipleObserverMultipleStartEndEvents);
   FRIEND_TEST_ALL_PREFIXES(DataUseTabModelTest, TabCloseEvent);
   FRIEND_TEST_ALL_PREFIXES(DataUseTabModelTest, TabCloseEventEndsTracking);
   FRIEND_TEST_ALL_PREFIXES(DataUseTabModelTest,
                            CompactTabEntriesWithinMaxLimit);
 
   typedef base::hash_map<int32_t, TabDataUseEntry> TabEntryMap;
 
   // Returns the maximum number of tab entries to maintain session information
   // about.
   static size_t GetMaxTabEntriesForTests();
 
-  // Notifies the observers that a data usage tracking session started for
-  // |tab_id|.
-  void NotifyObserversOfTrackingStarting(int32_t tab_id);
-
-  // Notifies the observers that an active data usage tracking session ended for
-  // |tab_id|.
-  void NotifyObserversOfTrackingEnding(int32_t tab_id);
-
   // Initiates a new tracking session with the |label| for tab with id |tab_id|.
   void StartTrackingDataUse(int32_t tab_id, const std::string& label);
 
   // Ends the current tracking session for tab with id |tab_id|.
   void EndTrackingDataUse(int32_t tab_id);
 
   // Compacts the tab entry map |active_tabs_| by removing expired tab entries.
   // After removing expired tab entries, if the size of |active_tabs_| exceeds
   // |kMaxTabEntries|, oldest unexpired tab entries will be removed until its
   // size is |kMaxTabEntries|.
   void CompactTabEntries();
 
   // Contains the ExternalDataUseObserver. The caller must ensure that the
   // |data_use_observer_| outlives this instance.
   const ExternalDataUseObserver* data_use_observer_;
 
   // List of observers waiting for tracking session start and end notifications.
-  const scoped_refptr<base::ObserverListThreadSafe<TabDataUseObserver>>
-      observer_list_;
+  base::ObserverList<TabDataUseObserver> observer_list_;
 
   // Maintains the tracking sessions of multiple tabs.
   TabEntryMap active_tabs_;
 
   base::ThreadChecker thread_checker_;
 
-  // |weak_factory_| is used for generating weak pointers to be passed to
-  // DataUseTabUIManager on the UI thread.
   base::WeakPtrFactory<DataUseTabModel> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DataUseTabModel);
 };
 
 }  // namespace android
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_ANDROID_DATA_USAGE_DATA_USE_TAB_MODEL_H_