Change WebBluetooth chooser OK button's label to be "Pair"

chrome/browser/ui/bluetooth/bluetooth_chooser_controller.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_UI_BLUETOOTH_BLUETOOTH_CHOOSER_CONTROLLER_H_
 #define CHROME_BROWSER_UI_BLUETOOTH_BLUETOOTH_CHOOSER_CONTROLLER_H_
 
 #include <stddef.h>
 
 #include <string>
@@ skipping 10 matching lines @@
 // It can be used by WebBluetooth API to get the user's permission to
 // access a Bluetooth device. It is owned by ChooserBubbleDelegate.
 class BluetoothChooserController : public ChooserController {
  public:
   explicit BluetoothChooserController(
       content::RenderFrameHost* owner,
       const content::BluetoothChooser::EventHandler& event_handler);
   ~BluetoothChooserController() override;
 
   // ChooserController:
+  base::string16 GetOkButtonLabel() const override;
   size_t NumOptions() const override;
   base::string16 GetOption(size_t index) const override;
   void Select(size_t index) override;
   void Cancel() override;
   void Close() override;
   void OpenHelpCenterUrl() const override;
 
   // Shows a new device in the chooser.
   void AddDevice(const std::string& device_id,
                  const base::string16& device_name);
 
   // Tells the chooser that a device is no longer available.
   void RemoveDevice(const std::string& device_id);
 
  private:
   // 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_;
 
   DISALLOW_COPY_AND_ASSIGN(BluetoothChooserController);
 };
 
 #endif  // CHROME_BROWSER_UI_BLUETOOTH_BLUETOOTH_CHOOSER_CONTROLLER_H_