Update shelf spacing in Chrome OS according to the MD specs

ash/root_window_controller_unittest.cc

 // 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 "ash/root_window_controller.h"
 
 #include <memory>
 
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/shell_window_ids.h"
@@ skipping 181 matching lines @@
   UpdateDisplay("600x600");
 
   // d2 must have been deleted.
   EXPECT_FALSE(tracker.Contains(d2));
 
   EXPECT_EQ(root_windows[0], normal->GetNativeView()->GetRootWindow());
   EXPECT_EQ("100,20 100x100", normal->GetWindowBoundsInScreen().ToString());
   EXPECT_EQ("100,20 100x100",
             normal->GetNativeView()->GetBoundsInRootWindow().ToString());
 
-  // Maximized area on primary display has 47px (ash::kShelfSize) inset at the
-  // bottom.
+  // Maximized area on primary display has 47px for non-md and 48px for md
+  // (defined in ash::SHELF_SIZE) inset at the bottom.
 
   // First clear fullscreen status, since both fullscreen and maximized windows
   // share the same desktop workspace, which cancels the shelf status.
   fullscreen->SetFullscreen(false);
   EXPECT_EQ(root_windows[0], maximized->GetNativeView()->GetRootWindow());
   EXPECT_EQ("0,0 600x553", maximized->GetWindowBoundsInScreen().ToString());
   EXPECT_EQ("0,0 600x553",
             maximized->GetNativeView()->GetBoundsInRootWindow().ToString());
 
   // Set fullscreen to true, but maximized window's size won't change because
@@ skipping 829 matching lines @@
   keyboard_controller->ui()->GetKeyboardWindow()->SetBounds(
       gfx::Rect(0, 400, 800, 200));
   EXPECT_EQ("0,400 800x200", keyboard_container->bounds().ToString());
 
   UpdateDisplay("600x800");
   EXPECT_EQ("0,600 600x200", keyboard_container->bounds().ToString());
 }
 
 }  // namespace test
 }  // namespace ash