chromeos: converts ash devtools to aura::Window

ui/wm/public/activation_client.cc

Index: ui/wm/public/activation_client.cc
diff --git a/ui/wm/public/activation_client.cc b/ui/wm/public/activation_client.cc
index 85636c0b13df2ffa701f8466f9ed5b36933f1b08..fcf0173201c4aaf8e77948178f4e7ea92ebc577b 100644
--- a/ui/wm/public/activation_client.cc
+++ b/ui/wm/public/activation_client.cc
@@ -21,9 +21,14 @@ void SetActivationClient(Window* root_window, ActivationClient* client) {
   root_window->SetProperty(kRootWindowActivationClientKey, client);
 }
 
+const ActivationClient* GetActivationClient(const Window* root_window) {
+  return root_window ? root_window->GetProperty(kRootWindowActivationClientKey)
+                     : nullptr;
+}
+
 ActivationClient* GetActivationClient(Window* root_window) {
-  return root_window ?
-      root_window->GetProperty(kRootWindowActivationClientKey) : NULL;
+  return root_window ? root_window->GetProperty(kRootWindowActivationClientKey)
+                     : nullptr;
 }
 
 void SetHideOnDeactivate(Window* window, bool hide_on_deactivate) {