2 files changed, 22 insertions, 0 deletions
diff --git a/components/power/origin_power_map.cc b/components/power/origin_power_map.cc
index dfb0f17..4ce32e2 100644
--- a/components/power/origin_power_map.cc
+++ b/components/power/origin_power_map.cc
@@ -49,4 +49,14 @@ OriginPowerMap::PercentOriginMap OriginPowerMap::GetPercentOriginMap() {
   return percent_map;
 }
 
+scoped_ptr<OriginPowerMap::Subscription>
+OriginPowerMap::AddPowerConsumptionUpdatedCallback(
+    const base::Closure& callback) {
+  return callback_list_.Add(callback);
+}
+
+void OriginPowerMap::OnAllOriginsUpdated() {
+  callback_list_.Notify();
+}
+
 }  // namespace power
diff --git a/components/power/origin_power_map.h b/components/power/origin_power_map.h
index 0936be4..36caa02 100644
--- a/components/power/origin_power_map.h
+++ b/components/power/origin_power_map.h
@@ -7,6 +7,7 @@
 
 #include <map>
 
+#include "base/callback_list.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "url/gurl.h"
 
@@ -17,6 +18,7 @@ namespace power {
 class OriginPowerMap : public KeyedService {
  public:
   typedef std::map<GURL, int> PercentOriginMap;
+  typedef base::CallbackList<void(void)>::Subscription Subscription;
 
   OriginPowerMap();
   virtual ~OriginPowerMap();
@@ -33,6 +35,14 @@ class OriginPowerMap : public KeyedService {
   // consumed.
   PercentOriginMap GetPercentOriginMap();
 
+  // Adds a callback for the completion of a round of updates to |origin_map_|.
+  scoped_ptr<Subscription> AddPowerConsumptionUpdatedCallback(
+      const base::Closure& callback);
+
+  // Notifies observers to let them know that the origin power map has finished
+  // updating for all origins this cycle.
+  void OnAllOriginsUpdated();
+
  private:
   // OriginMap maps a URL to the amount of power consumed by the URL using the
   // same units as |total_consumed_|.
@@ -43,6 +53,8 @@ class OriginPowerMap : public KeyedService {
   // the power heuristics available to the platform.
   double total_consumed_;
 
+  base::CallbackList<void(void)> callback_list_;
+
   DISALLOW_COPY_AND_ASSIGN(OriginPowerMap);
 };