Web MIDI: implement permission infobar

chrome/browser/media/chrome_midi_permission_context.h

+// Copyright 2013 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 CHROME_BROWSER_MEDIA_CHROME_MIDI_PERMISSION_CONTEXT_H_
+#define CHROME_BROWSER_MEDIA_CHROME_MIDI_PERMISSION_CONTEXT_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "components/browser_context_keyed_service/browser_context_keyed_service.h"
+#include "content/public/browser/browser_context.h"
+
+class GURL;
+class PermissionQueueController;
+class PermissionRequestID;
+class Profile;
+
+// This class manages MIDI permissions flow. Used on the UI thread.
+class ChromeMIDIPermissionContext : public BrowserContextKeyedService {
+ public:
+  explicit ChromeMIDIPermissionContext(Profile* profile);
+  virtual ~ChromeMIDIPermissionContext();
+
+  // BrowserContextKeyedService methods:
+  virtual void Shutdown() OVERRIDE;
+
+  // Request to ask users permission about MIDI.
+  void RequestMIDISysExPermission(
+      int render_process_id,
+      int render_view_id,
+      const GURL& requesting_frame,
+      const content::BrowserContext::MIDISysExPermissionCallback& callback);
+
+ private:
+  // Decide whether the permission should be granted.
+  // Calls PermissionDecided if permission can be decided non-interactively,
+  // or NotifyPermissionSet if permission decided by presenting an infobar.
+  void DecidePermission(
+      const PermissionRequestID& id,
+      const GURL& requesting_frame,
+      const GURL& embedder,
+      const content::BrowserContext::MIDISysExPermissionCallback& callback);
+
+  // Called when permission is granted without interactively asking the user.
+  void PermissionDecided(
+      const PermissionRequestID& id,
+      const GURL& requesting_frame,
+      const GURL& embedder,
+      const content::BrowserContext::MIDISysExPermissionCallback& callback,
+      bool allowed);
+
+  // Called when the permission decision is made. It may be by the
+  // InfoBarDelegate to notify permission has been set.
+  void NotifyPermissionSet(
+      const PermissionRequestID& id,
+      const GURL& requesting_frame,
+      const content::BrowserContext::MIDISysExPermissionCallback& callback,
+      bool allowed);
+
+  // Return an instance of the infobar queue controller, creating it if needed.
+  PermissionQueueController* GetQueueController();
+
+  Profile* const profile_;
+  bool shutting_down_;
+  scoped_ptr<PermissionQueueController> permission_queue_controller_;
+
+  DISALLOW_COPY_AND_ASSIGN(ChromeMIDIPermissionContext);
+};
+
+#endif  // CHROME_BROWSER_MEDIA_CHROME_MIDI_PERMISSION_CONTEXT_H_