Revert 149869 because it broke ash_unittests on win_aura and linux_chromeos.

ash/shell_unittest.cc

Index: ash/shell_unittest.cc
===================================================================
--- ash/shell_unittest.cc	(revision 149877)
+++ ash/shell_unittest.cc	(working copy)
@@ -3,7 +3,6 @@
 // found in the LICENSE file.
 
 #include "ash/ash_switches.h"
-#include "ash/desktop_background/desktop_background_widget_controller.h"
 #include "ash/launcher/launcher.h"
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
@@ -59,8 +58,6 @@
   EXPECT_TRUE(Shell::GetContainer(
       root_window, internal::kShellWindowId_SystemModalContainer));
   EXPECT_TRUE(Shell::GetContainer(
-      root_window, internal::kShellWindowId_LockScreenBackgroundContainer));
-  EXPECT_TRUE(Shell::GetContainer(
       root_window, internal::kShellWindowId_LockScreenContainer));
   EXPECT_TRUE(Shell::GetContainer(
       root_window, internal::kShellWindowId_LockSystemModalContainer));
@@ -274,13 +271,8 @@
   EXPECT_EQ(Shell::GetPrimaryRootWindow()->GetHostSize().height(),
             launcher_widget->GetWindowBoundsInScreen().bottom());
   // We have a desktop background but not a bare layer.
-  // TODO (antrim): enable once we find out why it fails component build.
-  //  internal::DesktopBackgroundWidgetController* background =
-  //      Shell::GetPrimaryRootWindow()->
-  //          GetProperty(internal::kWindowDesktopComponent);
-  //  EXPECT_TRUE(background);
-  //  EXPECT_TRUE(background->widget());
-  //  EXPECT_FALSE(background->layer());
+  EXPECT_TRUE(test_api.root_window_layout()->background_widget());
+  EXPECT_FALSE(test_api.root_window_layout()->background_layer());
 
   // Create a normal window.  It is not maximized.
   views::Widget::InitParams widget_params(