Make DataUseTabModel and DataUseMatcher more independent

chrome/browser/android/data_usage/data_use_tab_model.h

Index: chrome/browser/android/data_usage/data_use_tab_model.h
diff --git a/chrome/browser/android/data_usage/data_use_tab_model.h b/chrome/browser/android/data_usage/data_use_tab_model.h
index cb28b01e3ff6f140c3b56678c9da67649e7214cf..893437721e7a404e386529f9929e1a35e70d5ac4 100644
--- a/chrome/browser/android/data_usage/data_use_tab_model.h
+++ b/chrome/browser/android/data_usage/data_use_tab_model.h
@@ -11,6 +11,7 @@
 #include <string>
 #include <vector>
 
+#include "base/callback.h"
 #include "base/containers/hash_tables.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
@@ -105,15 +106,12 @@ class DataUseTabModel {
   static const char kDefaultTag[];
   static const char kCustomTabTag[];
 
-  DataUseTabModel();
-
-  // Initializes |this| on UI thread. |external_data_use_observer_bridge| is the
-  // pointer to ExternalDataUseObserverBridge object. DataUseTabModel and
-  // ExternalDataUseObserverBridge objects are owned by ExternalDataUseObserver
-  // and DataUseTabModel is destroyed first followed by
-  // ExternalDataUseObserverBridge.
-  void InitOnUIThread(
-      const ExternalDataUseObserverBridge* external_data_use_observer_bridge);
+  // |fetch_matching_rules_callback| is the callback to be run to initiate
+  // fetching matching rules and |on_matching_rules_fetched_callback|
+  // is the callback to be run after matching rules are fetched.
+  DataUseTabModel(
+      const base::Closure& fetch_matching_rules_callback,

[tbansal1, 2016/07/19 17:59:32]

May be rename to |force_fetch_matching_rules_callback|
Right now, the names of the two callbacks are pretty similar, and it is slightly
confusing.

[tbansal1, 2016/07/19 17:59:32]

include callback_forward.h for base::Closure.

[Raj, 2016/07/19 21:29:08]

Done.

[Raj, 2016/07/19 21:29:08]

Done.

+      const base::Callback<void(bool)>& on_matching_rules_fetched_callback);
 
   virtual ~DataUseTabModel();
 
@@ -143,7 +141,7 @@ class DataUseTabModel {
   // Notifies the DataUseTabModel that tracking label |label| is removed. Any
   // active tracking sessions with the label are ended, without notifying any of
   // the TabDataUseObserver.
-  virtual void OnTrackingLabelRemoved(std::string label);
+  virtual void OnTrackingLabelRemoved(const std::string& label);
 
   // Gets the tracking information for the tab with id |tab_id| at time
   // |timestamp|. |output_info| must not be null. If a tab tracking session is
@@ -306,6 +304,9 @@ class DataUseTabModel {
   // Stores the matching patterns.
   std::unique_ptr<DataUseMatcher> data_use_matcher_;
 
+  // Callback to be run to initiate fetching the matching rules.
+  const base::Closure fetch_matching_rules_callback_;
+
   // True if DataUseTabModel is ready to process UI navigation events.
   // DataUseTabModel will be considered ready when the first rule fetch is
   // complete or the control app not installed callback was received, whichever