Remove the brightness control line from the uber tray bubble default view.

ash/system/brightness/tray_brightness.cc

Index: ash/system/brightness/tray_brightness.cc
diff --git a/ash/system/brightness/tray_brightness.cc b/ash/system/brightness/tray_brightness.cc
index 33ced238cb0e604b287680efb3c15135901c19ed..3c5e0401137dce1b0048e7146bcf985406a46c09 100644
--- a/ash/system/brightness/tray_brightness.cc
+++ b/ash/system/brightness/tray_brightness.cc
@@ -161,10 +161,7 @@ views::View* TrayBrightness::CreateTrayView(user::LoginStatus status) {
 }
 
 views::View* TrayBrightness::CreateDefaultView(user::LoginStatus status) {
-  CHECK(brightness_view_ == NULL);
-  brightness_view_ = new tray::BrightnessView(current_percent_);
-  is_default_view_ = true;
-  return brightness_view_;
+  return NULL;
 }
 
 views::View* TrayBrightness::CreateDetailedView(user::LoginStatus status) {