Revert of Make WindowState::CanMinimize() take into account WidgetDelegate::CanMinimize()

ash/wm/window_state.cc

 // Copyright 2013 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/wm/window_state.h"
 
 #include "ash/ash_switches.h"
 #include "ash/root_window_controller.h"
 #include "ash/screen_util.h"
 #include "ash/shell_window_ids.h"
@@ skipping 135 matching lines @@
     return false;
 
   if (!window()->delegate())
     return true;
 
   gfx::Size max_size = window_->delegate()->GetMaximumSize();
   return !max_size.width() && !max_size.height();
 }
 
 bool WindowState::CanMinimize() const {
-  return window()->GetProperty(aura::client::kCanMinimizeKey);
+  RootWindowController* controller = RootWindowController::ForWindow(window_);
+  if (!controller)
+    return false;
+  aura::Window* lockscreen =
+      controller->GetContainer(kShellWindowId_LockScreenContainersContainer);
+  if (lockscreen->Contains(window_))
+    return false;
+
+  return true;
 }
 
 bool WindowState::CanResize() const {
   return window_->GetProperty(aura::client::kCanResizeKey);
 }
 
 bool WindowState::CanActivate() const {
   return ::wm::CanActivateWindow(window_);
 }
 
@@ skipping 283 matching lines @@
   }
   return settings;
 }
 
 const WindowState* GetWindowState(const aura::Window* window) {
   return GetWindowState(const_cast<aura::Window*>(window));
 }
 
 }  // namespace wm
 }  // namespace ash