cros: Remove some OS platform ifdefs from ash

ash/tooltips/tooltip_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/shell.h"
 #include "ash/test/ash_test_base.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/aura/env.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
@@ skipping 138 matching lines @@
   // Show tooltip on second display.
   ui::test::EventGenerator generator(root_windows[1]);
   generator.MoveMouseRelativeTo(widget2->GetNativeView(),
                                 view2->bounds().CenterPoint());
   helper_->FireTooltipTimer();
   EXPECT_TRUE(helper_->IsTooltipVisible());
 
   // Get rid of secondary display. This destroy's the tooltip's aura window. If
   // we have handled this case, we will not crash in the following statement.
   UpdateDisplay("1000x600");
-#if !defined(OS_WIN)
-  // TODO(cpu): Detangle the window destruction notification. Currently
-  // the TooltipController::OnWindowDestroyed is not being called then the
-  // display is torn down so the tooltip is is still there.
   EXPECT_FALSE(helper_->IsTooltipVisible());
-#endif
   EXPECT_EQ(widget2->GetNativeView()->GetRootWindow(), root_windows[0]);
 
   // The tooltip should create a new aura window for itself, so we should still
   // be able to show tooltips on the primary display.
   ui::test::EventGenerator generator1(root_windows[0]);
   generator1.MoveMouseRelativeTo(widget1->GetNativeView(),
                                  view1->bounds().CenterPoint());
   helper_->FireTooltipTimer();
   EXPECT_TRUE(helper_->IsTooltipVisible());
 }
 
 }  // namespace test
 }  // namespace ash