Implement logging of features for bluetooth connections.

The code that calls the bluetooth logging function is in
https://chromium-review.googlesource.com/c/chromium/src/+/1999973.

Bug: 1014839
Change-Id: Ica03b6509df95b389559cb01a8f9dea4dcf15e82
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2011469Reviewed-by: Tony Yeoman <tby@chromium.org>
Commit-Queue: Rachel Wong <wrong@chromium.org>
Cr-Commit-Position: refs/heads/master@{#733885}

ash/system/machine_learning/user_settings_event.proto

@@ -102,9 +102,9 @@ message UserSettingsEvent {
     // Whether the user has connected to a cellular network in the current
     // session.
     optional bool used_cellular_in_session = 17;
-    // Whether there are previously paired bluetooth devices available for
-    // connection.
-    optional bool has_available_bluetooth_devices = 18;
+    // Whether or not the current bluetooth device was already paired. Only
+    // populated upon connection to a bluetooth device.
+    optional bool is_paired_bluetooth_device = 18;
     // Whether the user has set up a night light schedule.
     optional bool has_night_light_schedule = 19;
     // True if it is after sunset and before sunrise in the local time.

ash/system/machine_learning/user_settings_event_logger.cc

@@ -62,11 +62,29 @@ void UserSettingsEventLogger::LogNetworkUkmEvent(
     // We are not interested in other types of networks.
     return;
   }
+  event->set_setting_type(UserSettingsEvent::Event::QUICK_SETTINGS);
+
+  PopulateSharedFeatures(&settings_event);
+  SendToUkm(settings_event);
+}
 
+void UserSettingsEventLogger::LogBluetoothUkmEvent(
+    const BluetoothAddress& device_address) {
+  UserSettingsEvent settings_event;
+  auto* const event = settings_event.mutable_event();
+
+  event->set_setting_id(UserSettingsEvent::Event::BLUETOOTH);
   event->set_setting_type(UserSettingsEvent::Event::QUICK_SETTINGS);
-  // Convert the setting state to an int. Some settings have multiple states, so
-  // all setting states are stored as ints.
-  event->set_current_value(1);
+
+  const auto& devices =
+      Shell::Get()->tray_bluetooth_helper()->GetAvailableBluetoothDevices();
+  for (const auto& device : devices) {
+    if (device->address == device_address) {
+      settings_event.mutable_features()->set_is_paired_bluetooth_device(
+          device->is_paired);
+      break;
+    }
+  }
 
   PopulateSharedFeatures(&settings_event);
   SendToUkm(settings_event);

ash/system/machine_learning/user_settings_event_logger.h

@@ -5,6 +5,7 @@
 #ifndef ASH_SYSTEM_MACHINE_LEARNING_USER_SETTINGS_EVENT_LOGGER_H_
 #define ASH_SYSTEM_MACHINE_LEARNING_USER_SETTINGS_EVENT_LOGGER_H_
 
+#include "ash/system/bluetooth/tray_bluetooth_helper.h"
 #include "ash/system/machine_learning/user_settings_event.pb.h"
 #include "chromeos/services/network_config/public/mojom/cros_network_config.mojom-forward.h"
 
@@ -27,6 +28,9 @@ class UserSettingsEventLogger {
   // Logs an event to UKM that the user has connected to the given network.
   void LogNetworkUkmEvent(
       const chromeos::network_config::mojom::NetworkStateProperties& network);
+  // Logs an event to UKM that the user has connected to the given bluetooth
+  // device.
+  void LogBluetoothUkmEvent(const BluetoothAddress& device_address);
 
  private:
   UserSettingsEventLogger();