Update the Website Settings page when the power consumption is updated.

components/power/origin_power_map_observer.h

Index: components/power/origin_power_map_observer.h
diff --git a/components/power/origin_power_map_observer.h b/components/power/origin_power_map_observer.h
new file mode 100644
index 0000000000000000000000000000000000000000..dd896fc6ba53a30f045ee96624df1c4723f9ebcd
--- /dev/null
+++ b/components/power/origin_power_map_observer.h
@@ -0,0 +1,18 @@
+// Copyright 2014 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 COMPONENTS_POWER_ORIGIN_POWER_MAP_OBSERVER_H_
+#define COMPONENTS_POWER_ORIGIN_POWER_MAP_OBSERVER_H_
+
+namespace power {
+
+class OriginPowerMapObserver {
+ public:
+  // Called when the origin power map is finished updating.
+  virtual void OnPowerConsumptionUpdated() = 0;

[Bernhard Bauer, 2014/08/29 19:16:31]

An alternative to a one-method interface is to use base::SubscriptionList and
callbacks.

[Daniel Nishi, 2014/09/02 16:30:30]

Would this require weak ptr factories for everyone who would go onto the
SubscriberList, though?

[Bernhard Bauer, 2014/09/02 16:39:57]

No, because the observer would destroy its SubscriptionList::Subscription when
it is destroyed itself, which unregisters.

[Daniel Nishi, 2014/09/02 17:10:08]

Ah, I understand.

I've updated the implementation to use a Subscription instead.

+};
+
+}  // namespace power
+
+#endif  // COMPONENTS_POWER_ORIGIN_POWER_MAP_OBSERVER_H_