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 2b60f2d86cd95d72330e2b949df2dfe0e03cc2bf..a541b45051d16bf06ae74bd3e185820e2daeaee0 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_forward.h"
 #include "base/containers/hash_tables.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
@@ -105,15 +106,17 @@ 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
+  // |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);
+  DataUseTabModel(
+      const base::Closure& fetch_matching_rules_callback,
+      const base::Callback<void(bool)>& on_matching_rules_fetched_callback);
+
+  // Initializes |this| on UI thread.
+  void InitOnUIThread();
 
   virtual ~DataUseTabModel();
 
@@ -143,7 +146,7 @@ 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
@@ -305,6 +308,9 @@ 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