Wires keeping the launcher up to date with the browser.

ui/aura/window.cc

Index: ui/aura/window.cc
diff --git a/ui/aura/window.cc b/ui/aura/window.cc
index d2735184b9c53690a14f18cb429355d01a4e27ab..a17c7e70be5c0d3245f654230d177b920d365f13 100644
--- a/ui/aura/window.cc
+++ b/ui/aura/window.cc
@@ -377,6 +377,9 @@ internal::RootWindow* Window::GetRoot() {
 }
 
 void Window::SetVisible(bool visible) {
+  if (visible == layer_->visible())
+    return;  // No change.
+
   bool was_visible = IsVisible();
   layer_->SetVisible(visible);
   bool is_visible = IsVisible();
@@ -385,6 +388,8 @@ void Window::SetVisible(bool visible) {
     if (delegate_)
       delegate_->OnWindowVisibilityChanged(is_visible);
   }
+  FOR_EACH_OBSERVER(WindowObserver, observers_,
+                    OnWindowVisibilityChanged(this, is_visible));
 }
 
 void Window::SchedulePaint() {