Remove docked windows entirely in M59.

ash/common/wm/mru_window_tracker_unittest.cc

Index: ash/common/wm/mru_window_tracker_unittest.cc
diff --git a/ash/common/wm/mru_window_tracker_unittest.cc b/ash/common/wm/mru_window_tracker_unittest.cc
index cf92338fbcd0dd262c335c0180e9b84a485ec4e2..99201fa5d1348d8bcaa927d742651813ad396d54 100644
--- a/ash/common/wm/mru_window_tracker_unittest.cc
+++ b/ash/common/wm/mru_window_tracker_unittest.cc
@@ -101,12 +101,6 @@ TEST_F(MruWindowTrackerTest, DraggedWindowsInListOnlyOnce) {
   w1->GetWindowState()->CreateDragDetails(
       gfx::Point(), HTRIGHT, aura::client::WINDOW_MOVE_SOURCE_TOUCH);
 
-  // During a drag the window is reparented by the Docked container.
-  WmWindow* drag_container = w1->GetRootWindow()->GetChildByShellWindowId(
-      kShellWindowId_DockedContainer);
-  drag_container->AddChild(w1);
-  EXPECT_TRUE(w1->GetWindowState()->is_dragged());
-
   // The dragged window should only be in the list once.
   WmWindow::Windows window_list =
       mru_window_tracker()->BuildWindowListIgnoreModal();