views: Move layout_manager.[cc,h] into layout directory.

views/grid_layout.h

 // Copyright (c) 2011 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 VIEWS_GRID_LAYOUT_H_
 #define VIEWS_GRID_LAYOUT_H_
 #pragma once
 
 #include <string>
 #include <vector>
 
-#include "views/layout_manager.h"
+#include "views/layout/layout_manager.h"
 #include "views/view.h"
 
 namespace gfx {
 class Insets;
 }
 
 // GridLayout is a LayoutManager that positions child Views in a grid. You
 // define the structure of the Grid first, then add the Views.
 // The following creates a trivial grid with two columns separated by
 // a column with padding:
@@ skipping 339 matching lines @@
   // The master column of those columns that are linked. See Column
   // for a description of what the master column is.
   std::vector<Column*> master_columns_;
 
   DISALLOW_COPY_AND_ASSIGN(ColumnSet);
 };
 
 }  // namespace views
 
 #endif  // VIEWS_GRID_LAYOUT_H_