Keyboard Lock Host implementation

components/keyboard_lock/key_event_filter_installer.h

Index: components/keyboard_lock/key_event_filter_installer.h
diff --git a/components/keyboard_lock/key_event_filter_installer.h b/components/keyboard_lock/key_event_filter_installer.h
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index 0000000000000000000000000000000000000000..64a39f97faa32a11f0bfd515c28c2311f30dc550
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+++ b/components/keyboard_lock/key_event_filter_installer.h
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+// Copyright 2017 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_KEYBOARD_LOCK_KEY_EVENT_FILTER_INSTALLER_H_
+#define COMPONENTS_KEYBOARD_LOCK_KEY_EVENT_FILTER_INSTALLER_H_
+
+#include "base/macros.h"
+#include "components/keyboard_lock/key_event_filter.h"
+#include "components/keyboard_lock/key_event_filter_receiver.h"
+
+namespace keyboard_lock {
+
+// Installs itself as the default implementation of KeyEventFilter in
+// KeyEventFilterReceiver.
+class KeyEventFilterInstaller : public KeyEventFilter {
+ public:
+  ~KeyEventFilterInstaller() override;
+
+ protected:
+  // Creates a new instance of KeyEventFilterInstaller and installs it into
+  // |receiver|. The ownership of this instance of KeyEventFilterInstaller
+  // should be taken by KeyEventFilterReceiver but not consumers.
+  explicit KeyEventFilterInstaller(KeyEventFilterReceiver* receiver);
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(KeyEventFilterInstaller);
+};
+
+}  // namespace keyboard_lock
+
+#endif  // COMPONENTS_KEYBOARD_LOCK_KEY_EVENT_FILTER_INSTALLER_H_