Fix the logic of counting the number of devices for Web Bluetooth chooser UMA

content/browser/bluetooth/bluetooth_device_chooser_controller.cc

 // Copyright 2016 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.
 
 #include "content/browser/bluetooth/bluetooth_device_chooser_controller.h"
 
 #include <set>
 #include <string>
 #include <unordered_set>
 
@@ skipping 390 matching lines @@
     return;
   }
 
   if (!chooser_->CanAskForScanningPermission()) {
     VLOG(1) << "Closing immediately because Chooser cannot obtain permission.";
     OnBluetoothChooserEvent(BluetoothChooser::Event::DENIED_PERMISSION,
                             "" /* device_address */);
     return;
   }
 
+  device_ids_.clear();
   PopulateConnectedDevices();
   if (!chooser_.get()) {
     // If the dialog's closing, no need to do any of the rest of this.
     return;
   }
 
   if (!adapter_->IsPowered()) {
     chooser_->SetAdapterPresence(
         BluetoothChooser::AdapterPresence::POWERED_OFF);
     return;
@@ skipping 77 matching lines @@
 
 void BluetoothDeviceChooserController::StartDeviceDiscovery() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
 
   if (discovery_session_.get() && discovery_session_->IsActive()) {
     // Already running; just increase the timeout.
     discovery_session_timer_.Reset();
     return;
   }
 
-  device_ids_.clear();
-
   scanning_start_time_ = base::TimeTicks::Now();
 
   chooser_->ShowDiscoveryState(BluetoothChooser::DiscoveryState::DISCOVERING);
   adapter_->StartDiscoverySessionWithFilter(
       ComputeScanFilter(options_->filters),
       base::Bind(
           &BluetoothDeviceChooserController::OnStartDiscoverySessionSuccess,
           weak_ptr_factory_.GetWeakPtr()),
       base::Bind(
           &BluetoothDeviceChooserController::OnStartDiscoverySessionFailed,
@@ skipping 37 matching lines @@
 void BluetoothDeviceChooserController::OnBluetoothChooserEvent(
     BluetoothChooser::Event event,
     const std::string& device_address) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   // Shouldn't recieve an event from a closed chooser.
   DCHECK(chooser_.get());
 
   switch (event) {
     case BluetoothChooser::Event::RESCAN:
       RecordRequestDeviceOutcome(OutcomeFromChooserEvent(event));
+      device_ids_.clear();
       PopulateConnectedDevices();
       DCHECK(chooser_);
       StartDeviceDiscovery();
       // No need to close the chooser so we return.
       return;
     case BluetoothChooser::Event::DENIED_PERMISSION:
       RecordRequestDeviceOutcome(OutcomeFromChooserEvent(event));
       PostErrorCallback(blink::mojom::WebBluetoothResult::
                             CHOOSER_NOT_SHOWN_USER_DENIED_PERMISSION_TO_SCAN);
       break;
@@ skipping 39 matching lines @@
 
 void BluetoothDeviceChooserController::PostErrorCallback(
     blink::mojom::WebBluetoothResult error) {
   if (!base::ThreadTaskRunnerHandle::Get()->PostTask(
           FROM_HERE, base::Bind(error_callback_, error))) {
     LOG(WARNING) << "No TaskRunner.";
   }
 }
 
 }  // namespace content