Convert KeyboardDrivenEventRewriter to a ui::EventRewriter.

chrome/browser/chromeos/events/event_rewriter_controller.h

+// 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 CHROME_BROWSER_CHROMEOS_EVENTS_EVENT_REWRITER_CONTROLLER_H_
+#define CHROME_BROWSER_CHROMEOS_EVENTS_EVENT_REWRITER_CONTROLLER_H_
+
+#include <list>
+#include <vector>
+
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/scoped_vector.h"
+#include "ui/aura/env_observer.h"
+#include "ui/events/event_rewriter.h"
+
+namespace ui {
+class EventSource;
+}  // namespace ui
+
+namespace chromeos {
+
+// Owns |ui::EventRewriter|s and ensures that they are added to all root
+// windows |EventSource|s, current and future, in the order that they are
+// added to this.

[kpschoedel, 2014/04/22 19:53:08]

Changed to have one EventRewriterController handle all associated rewriters
instead of one each, because it is this that is informed of new root windows
(i.e. |EventSource|s) and rewriters have an order.

+class EventRewriterController : public aura::EnvObserver {
+ public:
+  explicit EventRewriterController();

[sadrul, 2014/04/23 19:32:53]

Don't need explicit

[kpschoedel, 2014/04/23 21:33:15]

Done. (Previous version had 1 arg.)

+  virtual ~EventRewriterController();
+
+  // Takes ownership of an EventRewriter; can only be called before Init().
+  void AddEventRewriter(scoped_ptr<ui::EventRewriter> rewriter);
+
+  // Add rewriters to any existing root windows; must be called once only
+  // after ash::Shell has been initialized.

[sadrul, 2014/04/23 19:32:53]

I am curious to know why this is necessary. Is it because we create this
controller before we create the ash::Shell?

[kpschoedel, 2014/04/23 21:33:15]

Partly, but more to ensure that all rewriters have been registered before they
are added to the existing root windows.

+  void Init();
+
+  void Shutdown();

[sadrul, 2014/04/23 19:32:53]

Document (Destroys and removes all event-rewriters?)

[kpschoedel, 2014/04/23 21:33:15]

Done.

+
+  // aura::EnvObserver overrides:
+  virtual void OnWindowInitialized(aura::Window* window) OVERRIDE {}
+  virtual void OnHostInitialized(aura::WindowTreeHost* host) OVERRIDE;
+
+ private:
+  typedef std::list<ui::EventSource*> EventSourceList;
+  typedef ScopedVector<ui::EventRewriter> EventRewriters;
+
+  void AddToEventSource(ui::EventSource* source);
+
+  // The |EventRewriter|s managed by this controller.
+  EventRewriters rewriters_;
+
+  // Whether the owned event rewriters have been added to existing
+  // root windows; after this no more rewriters can be added.
+  bool initialized_;
+
+  // Whether the owned event rewriters get added to new root windows.
+  bool operational_;
+
+  DISALLOW_COPY_AND_ASSIGN(EventRewriterController);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_EVENTS_EVENT_REWRITER_CONTROLLER_H_