Refactors DockedWindowLayoutManager in terms of ash/wm/common

ash/wm/common/shelf/wm_shelf_constants.cc

Index: ash/wm/common/shelf/wm_shelf_constants.cc
diff --git a/ash/wm/common/shelf/wm_shelf_constants.cc b/ash/wm/common/shelf/wm_shelf_constants.cc
new file mode 100644
index 0000000000000000000000000000000000000000..fa0425c97a671ec2b850a611e87ee3aa395e90e6
--- /dev/null
+++ b/ash/wm/common/shelf/wm_shelf_constants.cc
@@ -0,0 +1,14 @@
+// Copyright 2016 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 "ash/wm/common/shelf/wm_shelf_constants.h"
+
+namespace ash {
+namespace wm {
+
+const int kShelfBackgroundAlpha = 204;
+const int kTimeToSwitchBackgroundMs = 1000;
+
+}  // namespace wm
+}  // namespace ash