Moterm part 4: Add input event -> input character conversion function.

apps/moterm/key_util.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 APPS_MOTERM_KEY_UTIL_H_
+#define APPS_MOTERM_KEY_UTIL_H_
+
+#include <string>
+
+namespace mojo {
+class Event;
+}
+
+// Gets an appropriate sequence of characters to generate for the given key
+// pressed event (|key_event| must have |action| value
+// |EVENT_TYPE_KEY_PRESSED|). (Here, "appropriate" means VT100/xterm-ish.)
+std::string GetInputSequenceForKeyPressedEvent(const mojo::Event& key_event);
+
+#endif  // APPS_MOTERM_KEY_UTIL_H_