Add UMA for the number of devices in the chooser when a device is paired

content/shell/browser/layout_test/layout_test_bluetooth_chooser_factory.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 CONTENT_SHELL_BROWSER_LAYOUT_TEST_LAYOUT_TEST_BLUETOOTH_CHOOSER_FACTORY_H_
 #define CONTENT_SHELL_BROWSER_LAYOUT_TEST_LAYOUT_TEST_BLUETOOTH_CHOOSER_FACTORY_H_
 
 #include <memory>
 #include <set>
 #include <vector>
 
 #include "base/memory/weak_ptr.h"
 #include "content/public/browser/bluetooth_chooser.h"
 
 namespace content {
 
 class RenderFrameHost;
 
 class LayoutTestBluetoothChooserFactory {
  public:
   LayoutTestBluetoothChooserFactory();
   ~LayoutTestBluetoothChooserFactory();
 
   std::unique_ptr<BluetoothChooser> RunBluetoothChooser(
       RenderFrameHost* frame,
-      const BluetoothChooser::EventHandler& event_handler);
+      const BluetoothChooser::EventHandler& event_handler,
+      bool accept_all_devices);
 
   std::vector<std::string> GetAndResetEvents();
 
   void SendEvent(BluetoothChooser::Event event, const std::string& device_id);
 
  private:
   class Chooser;
 
   std::vector<std::string> events_;
 
   // Contains the set of live choosers, in order to send them events.
   std::set<Chooser*> choosers_;
 
   base::WeakPtrFactory<LayoutTestBluetoothChooserFactory> weak_this_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_SHELL_BROWSER_LAYOUT_TEST_LAYOUT_TEST_BLUETOOTH_CHOOSER_FACTORY_H_