Adds special support to the device manager for keyboards devices.

ui/events/input_device.cc

Index: ui/events/input_device.cc
diff --git a/ui/events/input_device.cc b/ui/events/input_device.cc
new file mode 100644
index 0000000000000000000000000000000000000000..bc4be862b414bc1fa684fc9b93aea60bba1eccc3
--- /dev/null
+++ b/ui/events/input_device.cc
@@ -0,0 +1,18 @@
+// 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.
+
+#include "ui/events/input_device.h"
+
+#include <string>
+
+namespace ui {
+
+// static
+const int InputDevice::kInvalidId = 0;
+
+InputDevice::InputDevice(int id, InputDeviceType type,
+    const std::string& name) : id(id), type(type), name(name) {
+}
+
+}  // namespace ui