Not submitted - Fixing invalid visibility states with layers which showed up in unittests ...

ash/wm/overview/window_selector_panels.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/overview/window_selector_panels.h"
 
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ash/wm/overview/scoped_transform_overview_window.h"
 #include "ash/wm/panels/panel_layout_manager.h"
@@ skipping 40 matching lines @@
 }
 
 ScopedTransformPanelWindow::~ScopedTransformPanelWindow() {
   // window() will be NULL if the window was destroyed.
   if (window())
     RestoreCallout();
 }
 
 void ScopedTransformPanelWindow::PrepareForOverview() {
   ScopedTransformOverviewWindow::PrepareForOverview();
-  GetCalloutWidget()->GetLayer()->SetOpacity(0.0f);
+  // The window is logically visible and we cannot make the layer fade to
+  // alpha=0. We therefore provide a float value which will result in a
+  // byte value of 0 but gets detected as not 0.
+  GetCalloutWidget()->GetLayer()->SetOpacity(0.001f);
 }
 
 views::Widget* ScopedTransformPanelWindow::GetCalloutWidget() {
   DCHECK(window()->parent()->id() == internal::kShellWindowId_PanelContainer);
   internal::PanelLayoutManager* panel_layout_manager =
       static_cast<internal::PanelLayoutManager*>(
           window()->parent()->layout_manager());
   return panel_layout_manager->GetCalloutWidgetForPanel(window());
 }
 
@@ skipping 100 matching lines @@
     transform.Translate(bounding_rect.x() - bounds.x(),
                         bounding_rect.y() - bounds.y());
     transform.PreconcatTransform(bounding_transform);
     transform.Translate(bounds.x() - bounding_rect.x(),
                         bounds.y() - bounding_rect.y());
     (*iter)->SetTransform(root_window, transform, animate);
   }
 }
 
 }  // namespace ash