[ash-md] Makes sure that minimized windows can be activated in overview

ash/common/wm/overview/scoped_transform_overview_window.cc

Index: ash/common/wm/overview/scoped_transform_overview_window.cc
diff --git a/ash/common/wm/overview/scoped_transform_overview_window.cc b/ash/common/wm/overview/scoped_transform_overview_window.cc
index cf808310e9721ef94d1661b342c9ede6a6454978..393b02ac9b4b6a900f6ab929ca1bc7c5d8a8b441 100644
--- a/ash/common/wm/overview/scoped_transform_overview_window.cc
+++ b/ash/common/wm/overview/scoped_transform_overview_window.cc
@@ -446,8 +446,13 @@ WmWindow* ScopedTransformOverviewWindow::GetOverviewWindow() const {
   return window_;
 }
 
+void ScopedTransformOverviewWindow::EnsureVisible() {
+  original_opacity_ = 1.f;
+}
+
 void ScopedTransformOverviewWindow::OnGestureEvent(ui::GestureEvent* event) {
   if (event->type() == ui::ET_GESTURE_TAP) {
+    EnsureVisible();
     window_->Show();
     window_->Activate();
   }
@@ -455,6 +460,7 @@ void ScopedTransformOverviewWindow::OnGestureEvent(ui::GestureEvent* event) {
 
 void ScopedTransformOverviewWindow::OnMouseEvent(ui::MouseEvent* event) {
   if (event->type() == ui::ET_MOUSE_PRESSED && event->IsOnlyLeftMouseButton()) {
+    EnsureVisible();
     window_->Show();
     window_->Activate();
   }