Don't treat minimized windows as lower priority in MRU list (for Alt+Tab

ash/common/wm/overview/window_grid.h

Index: ash/common/wm/overview/window_grid.h
diff --git a/ash/common/wm/overview/window_grid.h b/ash/common/wm/overview/window_grid.h
index cce8557c6d6c078f1beb9d27c095f5845cdd5f05..25f378847ca38e69dc94aa6b597d46339028d28d 100644
--- a/ash/common/wm/overview/window_grid.h
+++ b/ash/common/wm/overview/window_grid.h
@@ -15,6 +15,7 @@
 #include "ash/common/wm_window_observer.h"
 #include "base/macros.h"
 #include "base/memory/scoped_vector.h"
+#include "base/scoped_observer.h"
 
 namespace views {
 class Widget;
@@ -172,8 +173,7 @@ class ASH_EXPORT WindowGrid : public WmWindowObserver {
   // Vector containing all the windows in this grid.
   ScopedVector<WindowSelectorItem> window_list_;
 
-  // Vector containing the observed windows.
-  std::set<WmWindow*> observed_windows_;
+  ScopedObserver<WmWindow, WindowGrid> window_observer_;
 
   // Widget that darkens the screen background.
   std::unique_ptr<views::Widget> shield_widget_;
@@ -190,6 +190,9 @@ class ASH_EXPORT WindowGrid : public WmWindowObserver {
   // Number of columns in the grid.
   size_t num_columns_;
 
+  // True only after all windows have been prepared for overview.
+  bool prepared_for_overview_;
+
   DISALLOW_COPY_AND_ASSIGN(WindowGrid);
 };