Make DataUseTabModel and DataUseMatcher more independent

chrome/browser/android/data_usage/data_use_matcher.cc

Index: chrome/browser/android/data_usage/data_use_matcher.cc
diff --git a/chrome/browser/android/data_usage/data_use_matcher.cc b/chrome/browser/android/data_usage/data_use_matcher.cc
index be21c004ae8952ba04856282268896dbfb01b45e..b00c9e7ba55ef2b2a0ca2f4c9a3d8536be30aac3 100644
--- a/chrome/browser/android/data_usage/data_use_matcher.cc
+++ b/chrome/browser/android/data_usage/data_use_matcher.cc
@@ -16,7 +16,6 @@
 #include "base/time/default_tick_clock.h"
 #include "base/time/tick_clock.h"
 #include "base/time/time.h"
-#include "chrome/browser/android/data_usage/external_data_use_observer_bridge.h"
 #include "third_party/re2/src/re2/re2.h"
 #include "url/gurl.h"
 
@@ -25,15 +24,20 @@ namespace chrome {
 namespace android {
 
 DataUseMatcher::DataUseMatcher(
-    const base::WeakPtr<DataUseTabModel>& data_use_tab_model,
-    const ExternalDataUseObserverBridge* external_data_use_observer_bridge,
+    const base::Callback<void(const std::string&)>&
+        on_tracking_label_removed_callback,
+    const base::Callback<void(bool)>& on_matching_rules_fetched_callback,
     const base::TimeDelta& default_matching_rule_expiration_duration)
-    : data_use_tab_model_(data_use_tab_model),
-      default_matching_rule_expiration_duration_(
+    : default_matching_rule_expiration_duration_(
           default_matching_rule_expiration_duration),
       tick_clock_(new base::DefaultTickClock()),
-      external_data_use_observer_bridge_(external_data_use_observer_bridge) {
-  DCHECK(external_data_use_observer_bridge_);
+      on_tracking_label_removed_callback_(on_tracking_label_removed_callback),
+      on_matching_rules_fetched_callback_(on_matching_rules_fetched_callback) {
+  DCHECK(on_tracking_label_removed_callback_);
+  DCHECK(on_matching_rules_fetched_callback_);
+  // Detach from current thread since rest of DataUseMatcher lives on the UI
+  // thread and the current thread may not be UI thread..
+  thread_checker_.DetachFromThread();
 }
 
 DataUseMatcher::~DataUseMatcher() {}
@@ -82,17 +86,15 @@ void DataUseMatcher::RegisterURLRegexes(
     removed_matching_rule_labels.erase(labels.at(i));
   }
 
-  for (const std::string& label : removed_matching_rule_labels) {
-    if (data_use_tab_model_)
-      data_use_tab_model_->OnTrackingLabelRemoved(label);
-  }
+  for (const std::string& label : removed_matching_rule_labels)
+    on_tracking_label_removed_callback_.Run(label);
+
   UMA_HISTOGRAM_COUNTS_100("DataUsage.MatchingRulesCount.Valid",
                            matching_rules_.size());
   UMA_HISTOGRAM_COUNTS_100("DataUsage.MatchingRulesCount.Invalid",
                            invalid_rules);
 
-  external_data_use_observer_bridge_->ShouldRegisterAsDataUseObserver(
-      !matching_rules_.empty());
+  on_matching_rules_fetched_callback_.Run(!matching_rules_.empty());
 }
 
 bool DataUseMatcher::MatchesURL(const GURL& url, std::string* label) const {
@@ -140,11 +142,6 @@ bool DataUseMatcher::MatchesAppPackageName(const std::string& app_package_name,
   return false;
 }
 
-void DataUseMatcher::FetchMatchingRules() {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  external_data_use_observer_bridge_->FetchMatchingRules();
-}
-
 bool DataUseMatcher::HasRules() const {
   return !matching_rules_.empty();
 }