Wake Lock API implementation (Chromium part)

content/browser/wake_lock/wake_lock_service_context.h

+// Copyright 2015 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 CONTENT_BROWSER_WAKE_LOCK_WAKE_LOCK_DISPATCHER_HOST_H_
+#define CONTENT_BROWSER_WAKE_LOCK_WAKE_LOCK_DISPATCHER_HOST_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "base/observer_list.h"
+#include "content/browser/wake_lock/wake_lock_service_impl.h"
+#include "content/browser/wake_lock/wake_lock_state.h"
+#include "content/common/content_export.h"
+#include "content/public/browser/web_contents_observer.h"
+
+namespace content {
+
+class PowerSaveBlocker;
+class RenderFrameHost;
+class WebContents;
+
+class CONTENT_EXPORT WakeLockServiceContext
+    : public WebContentsObserver,
+      public WakeLockServiceImpl::WakeLockServiceCallback {
+ public:
+  explicit WakeLockServiceContext(WebContents* web_contents);
+  ~WakeLockServiceContext() override;
+
+  // WebContentsObserver implementation.
+  void RenderFrameCreated(RenderFrameHost* render_frame_host) override;
+  void RenderFrameDeleted(RenderFrameHost* render_frame_host) override;
+  void RenderFrameHostChanged(RenderFrameHost* old_host,
+                              RenderFrameHost* new_host) override;
+
+  // WakeLockServiceImpl::WakeLockServiceCallback implementation.
+  void RequestWakeLock(RenderFrameHost* render_frame_host) override;
+  void CancelWakeLock(RenderFrameHost* render_frame_host) override;
+
+  bool has_blocker_for_testing() const {
+    return blocker_;
+  }
+
+  class CONTENT_EXPORT Observer {

[mlamouri (slow - plz ping), 2015/08/21 10:03:35]

Not sure what the Observer is here for.

[alogvinov, 2015/08/26 14:47:19]

It was needed for the browser test, but I figured out how to do without it, so
removing this.

+   public:
+    virtual void OnUpdate() = 0;
+  };
+
+  void AddObserver(Observer* obs) {
+    observer_list_.AddObserver(obs);
+  }
+
+  void RemoveObserver(Observer* obs) {
+    observer_list_.RemoveObserver(obs);
+  }
+
+ private:
+  void CreateBlocker();
+  void RemoveBlocker();
+  void UpdateBlocker();
+
+  void NotifyUpdate();
+
+  WakeLockState wake_lock_state_;

[mlamouri (slow - plz ping), 2015/08/21 10:03:35]

Instead of WakeLockState, couldn't you simply have a std::set<> of RFH here? It
seems that it would be more or less the same thing, right?

Basically, have frames_requesting_lock_ in here instead of in WakeLockState.

[alogvinov, 2015/08/26 14:47:19]

Done.

+
+  scoped_ptr<PowerSaveBlocker> blocker_;

[mlamouri (slow - plz ping), 2015/08/21 10:03:35]

FWIW, I think the blocker_ name is hard to grasp.

[alogvinov, 2015/08/26 14:47:19]

Done.

+  base::ObserverList<Observer> observer_list_;
+
+  friend class WakeLockServiceContextTest;
+
+  base::WeakPtrFactory<WakeLockServiceContext> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(WakeLockServiceContext);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_WAKE_LOCK_WAKE_LOCK_DISPATCHER_HOST_H_