Revert of Add a row in the network tray to inform users to turn Bluetooth on to enable Tether.

ash/system/tray/tray_details_view.h

Index: ash/system/tray/tray_details_view.h
diff --git a/ash/system/tray/tray_details_view.h b/ash/system/tray/tray_details_view.h
index 764892da895eb832c3569c94d0f0cb5a73788b6f..e7f3162b7ef1ff20aea6245aca0f6fbdb28b9259 100644
--- a/ash/system/tray/tray_details_view.h
+++ b/ash/system/tray/tray_details_view.h
@@ -22,6 +22,7 @@
 namespace views {
 class BoxLayout;
 class CustomButton;
+class Label;
 class ProgressBar;
 class ScrollView;
 }  // namespace views
@@ -51,6 +52,22 @@
   SystemTrayItem* owner() { return owner_; }
 
  protected:
+  // A view containing only a label, which is to be inserted as a non-targetable
+  // row within a system menu detailed view (e.g., the "Scanning for devices..."
+  // message that can appear at the top of the Bluetooth detailed view).
+  class InfoLabel : public View {
+   public:
+    explicit InfoLabel(int message_id);
+    ~InfoLabel() override;
+
+    void SetMessage(int message_id);
+
+   private:
+    views::Label* const label_;
+
+    DISALLOW_COPY_AND_ASSIGN(InfoLabel);
+  };
+
   // views::View:
   void Layout() override;
   int GetHeightForWidth(int width) const override;