Support Bluetooth batteries

There's currently no generic Bluetooth device type in UPower, so we get them of "unknown" type.
Check for whether it comes from Bluez to determine it's a Bluetooth battery.

Differential Revision: https://phabricator.kde.org/D17345

src/solid/devices/backends/fakehw/fakebattery.cpp

@@ -58,6 +58,8 @@ Solid::Battery::BatteryType FakeBattery::type() const
         return Solid::Battery::CameraBattery;
     } else if (name == "gaminginput") {
         return Solid::Battery::GamingInputBattery;
+    } else if (name == "bluetooth") {
+        return Solid::Battery::BluetoothBattery;
     } else {
         return Solid::Battery::UnknownBattery;
     }

src/solid/devices/backends/upower/upowerbattery.cpp

@@ -74,6 +74,14 @@ Solid::Battery::BatteryType Battery::type() const
     case UP_DEVICE_KIND_GAMING_INPUT:
         result = Solid::Battery::GamingInputBattery;
         break;
+    case UP_DEVICE_KIND_UNKNOWN: {
+        // There is currently no "Bluetooth battery" type, so check if it comes from Bluez
+        if (m_device.data()->prop("NativePath").toString().startsWith(QLatin1String("/org/bluez/"))) {
+            result = Solid::Battery::BluetoothBattery;
+        }
+        break;
+    }
+
     }
     return result;
 }

src/solid/devices/backends/upower/upowerdevice.cpp

@@ -99,6 +99,11 @@ bool UPowerDevice::queryDeviceInterface(const Solid::DeviceInterface::Type &type
         case UP_DEVICE_KIND_GAMING_INPUT:
             return true;
         case UP_DEVICE_KIND_UNKNOWN:
+            // There is currently no "Bluetooth battery" type, so check if it comes from Bluez
+            if (prop("NativePath").toString().startsWith(QLatin1String("/org/bluez/"))) {
+                return true;
+            }
+            return false;
         case UP_DEVICE_KIND_LINE_POWER:
         case UP_DEVICE_KIND_MONITOR:
         case UP_DEVICE_KIND_MEDIA_PLAYER:

src/solid/devices/frontend/battery.h

@@ -75,12 +75,15 @@ public:
      * - PhoneBattery : A battery in a phone
      * - MonitorBattery : A battery in a monitor
      * - GamingInputBattery : A battery in a gaming input device (for example a wireless game pad)
+     * - BluetoothBattery: A generic Bluetooth device battery (if its type isn't known, a Bluetooth
+     *                     mouse would normally show up as a MouseBattery), @since 5.54
      * - UnknownBattery : A battery in an unknown device
      */
     enum BatteryType { UnknownBattery, PdaBattery, UpsBattery,
                        PrimaryBattery, MouseBattery, KeyboardBattery,
                        KeyboardMouseBattery, CameraBattery,
-                       PhoneBattery, MonitorBattery, GamingInputBattery
+                       PhoneBattery, MonitorBattery, GamingInputBattery,
+                       BluetoothBattery
                      };
     Q_ENUM(BatteryType)