Add throbber and status text to WebBluetooth chooser UI on non-Mac desktops

chrome/browser/ui/bluetooth/bluetooth_chooser_controller.h

Index: chrome/browser/ui/bluetooth/bluetooth_chooser_controller.h
diff --git a/chrome/browser/ui/bluetooth/bluetooth_chooser_controller.h b/chrome/browser/ui/bluetooth/bluetooth_chooser_controller.h
index deb2caa0d51ff883dca2280a269a90596a17cc2c..35becbf0630361bb1392d759fd1eaba6dca89104 100644
--- a/chrome/browser/ui/bluetooth/bluetooth_chooser_controller.h
+++ b/chrome/browser/ui/bluetooth/bluetooth_chooser_controller.h
@@ -28,14 +28,25 @@ class BluetoothChooserController : public ChooserController {
   ~BluetoothChooserController() override;
 
   // ChooserController:
+  base::string16 GetNoOptionsText() const override;
   base::string16 GetOkButtonLabel() const override;
   size_t NumOptions() const override;
   base::string16 GetOption(size_t index) const override;
+  void RefreshOptions() override;
+  base::string16 GetStatus() const override;
   void Select(size_t index) override;
   void Cancel() override;
   void Close() override;
   void OpenHelpCenterUrl() const override;
 
+  // Update the state of the Bluetooth adapter.
+  void OnAdapterPresenceChanged(
+      content::BluetoothChooser::AdapterPresence presence);
+
+  // Update the Bluetooth discovery state and let the user know whether
+  // discovery is happening.
+  void OnDiscoveryStateChanged(content::BluetoothChooser::DiscoveryState state);
+
   // Shows a new device in the chooser.
   void AddDevice(const std::string& device_id,
                  const base::string16& device_name);
@@ -44,11 +55,17 @@ class BluetoothChooserController : public ChooserController {
   void RemoveDevice(const std::string& device_id);
 
  private:
+  // Clears |device_names_and_ids_| and |device_name_map_|. Called when
+  // Bluetooth adapter is turned on or off, or when re-scan happens.
+  void ClearAllDevices();
+
   // Each pair is a (device name, device id).
   std::vector<std::pair<base::string16, std::string>> device_names_and_ids_;
   content::BluetoothChooser::EventHandler event_handler_;
   // Maps from device name to number of devices.
   std::unordered_map<base::string16, int> device_name_map_;
+  base::string16 no_devices_text_;
+  base::string16 status_text_;
 
   DISALLOW_COPY_AND_ASSIGN(BluetoothChooserController);
 };