Introduce App Launcher for Windows.

chrome/browser/ui/app_list/app_list_controller.cc

Index: chrome/browser/ui/app_list/app_list_controller.cc
diff --git a/chrome/browser/ui/app_list/app_list_controller.cc b/chrome/browser/ui/app_list/app_list_controller.cc
new file mode 100644
index 0000000000000000000000000000000000000000..687c09f4dea03c8e4cf6bf309157ed4934390d3a
--- /dev/null
+++ b/chrome/browser/ui/app_list/app_list_controller.cc
@@ -0,0 +1,16 @@
+// Copyright (c) 2012 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 "chrome/browser/ui/app_list/app_list_controller.h"
+
+#include "build/build_config.h"
+
+namespace app_list_controller {
+
+#if !defined(OS_WIN)
+// Default implementation for ports which do not have this implemented.
+void ShowAppList() {}
+#endif
+
+}  // namespace app_list_controller