Add unittest for ArcNotificationContentView

components/exo/surface.cc

Index: components/exo/surface.cc
diff --git a/components/exo/surface.cc b/components/exo/surface.cc
index b6edb5b7558d02bda6e326477945e107ffb6843d..90b44bdef684551d3f76eaa2f4722e7fcf74c5a9 100644
--- a/components/exo/surface.cc
+++ b/components/exo/surface.cc
@@ -182,12 +182,15 @@ class CustomWindowTargeter : public aura::WindowTargeter {
 
 }  // namespace
 
+// static
+const char Surface::kSurfaceWindowName[] = "ExoSurface";
+
 ////////////////////////////////////////////////////////////////////////////////
 // Surface, public:
 
 Surface::Surface() : window_(new aura::Window(new CustomWindowDelegate(this))) {
   window_->SetType(aura::client::WINDOW_TYPE_CONTROL);
-  window_->SetName("ExoSurface");
+  window_->SetName(kSurfaceWindowName);

[reveman, 2017/06/21 15:16:36]

We're going to remove |window_| soon to support MUS. Is there some other way we
can solve this? Can you add something to the NotificationSurface class?

[yoshiki, 2017/06/21 16:13:12]

Although I'm not sure how you remove |window_|, the window name
(kSurfaceWindowName) is just for DCHECK to ensure the window hierarchy. So, we
can safely just remove this when you remove |window_|.

[reveman, 2017/06/21 16:22:24]

Each surface will no longer have a window. Only the top-level delegate (e.g.
ShellSurface) will have a window. If the notification code rely on this window
then we need to start looking at how to avoid that asap.

If it's only for a DCHECK that we need to remove soon then I prefer not making
kSurfaceWindowName public.

   window_->SetProperty(kSurfaceKey, this);
   window_->Init(ui::LAYER_SOLID_COLOR);
   window_->SetEventTargeter(base::WrapUnique(new CustomWindowTargeter));