Add unit test for BluetoothChooserController

chrome/browser/ui/bluetooth/bluetooth_chooser_controller.cc

Index: chrome/browser/ui/bluetooth/bluetooth_chooser_controller.cc
diff --git a/chrome/browser/ui/bluetooth/bluetooth_chooser_controller.cc b/chrome/browser/ui/bluetooth/bluetooth_chooser_controller.cc
index 7f877bf6f4caab43e47c388910232fd4f8e3417c..14ccb0b25fda411030aacb811b1e4432e0fc98b2 100644
--- a/chrome/browser/ui/bluetooth/bluetooth_chooser_controller.cc
+++ b/chrome/browser/ui/bluetooth/bluetooth_chooser_controller.cc
@@ -234,6 +234,7 @@ void BluetoothChooserController::RemoveDevice(const std::string& device_id) {
                    });
 
   if (device_it != devices_.end()) {
+    size_t index = device_it - devices_.begin();
     devices_.erase(device_it);
 
     const auto& it = device_name_counts_.find(name_it->second);
@@ -246,7 +247,7 @@ void BluetoothChooserController::RemoveDevice(const std::string& device_id) {
     device_id_to_name_map_.erase(name_it);
 
     if (view())
-      view()->OnOptionRemoved(device_it - devices_.begin());
+      view()->OnOptionRemoved(index);
   }
 }