And here are my dbus messages with `sudo dbus-monitor --system`:


signal sender=:1.20 -> dest=(null destination) serial=1681 path=/org/bluez/hci0; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Adapter1"
   array [
      dict entry(
         string "Discovering"
         variant             boolean true
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1682 path=/; interface=org.freedesktop.DBus.ObjectManager; member=InterfacesAdded
   object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9"
   array [
      dict entry(
         string "org.freedesktop.DBus.Introspectable"
         array [
         ]
      )
      dict entry(
         string "org.bluez.Device1"
         array [
            dict entry(
               string "Address"
               variant                   string "70:70:B2:BD:79:C9"
            )
            dict entry(
               string "Name"
               variant                   string "Nexus 5X"
            )
            dict entry(
               string "Alias"
               variant                   string "Nexus 5X"
            )
            dict entry(
               string "Paired"
               variant                   boolean false
            )
            dict entry(
               string "Trusted"
               variant                   boolean false
            )
            dict entry(
               string "Blocked"
               variant                   boolean false
            )
            dict entry(
               string "LegacyPairing"
               variant                   boolean false
            )
            dict entry(
               string "RSSI"
               variant                   int16 -60
            )
            dict entry(
               string "Connected"
               variant                   boolean false
            )
            dict entry(
               string "UUIDs"
               variant                   array [
                     string "0000180f-0000-1000-8000-00805f9b34fb"
                  ]
            )
            dict entry(
               string "Adapter"
               variant                   object path "/org/bluez/hci0"
            )
            dict entry(
               string "TxPower"
               variant                   int16 -7
            )
         ]
      )
      dict entry(
         string "org.freedesktop.DBus.Properties"
         array [
         ]
      )
   ]
signal sender=:1.20 -> dest=(null destination) serial=1684 path=/; interface=org.freedesktop.DBus.ObjectManager; member=InterfacesAdded
   object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9"
   array [
      dict entry(
         string "org.chromium.BluetoothDevice"
         array [
         ]
      )
   ]
signal sender=:1.20 -> dest=(null destination) serial=1686 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Device1"
   array [
      dict entry(
         string "RSSI"
         variant             int16 -60
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1687 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Device1"
   array [
      dict entry(
         string "RSSI"
         variant             int16 -60
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1688 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Device1"
   array [
      dict entry(
         string "RSSI"
         variant             int16 -57
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1689 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Device1"
   array [
      dict entry(
         string "RSSI"
         variant             int16 -57
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1690 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Device1"
   array [
      dict entry(
         string "RSSI"
         variant             int16 -60
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1691 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Device1"
   array [
      dict entry(
         string "RSSI"
         variant             int16 -63
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1692 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Device1"
   array [
   ]
   array [
      string "TxPower"
      string "RSSI"
   ]
signal sender=:1.20 -> dest=(null destination) serial=1694 path=/org/bluez/hci0; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Adapter1"
   array [
      dict entry(
         string "Discovering"
         variant             boolean false
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1695 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Device1"
   array [
      dict entry(
         string "Connected"
         variant             boolean true
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1697 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Device1"
   array [
      dict entry(
         string "Trusted"
         variant             boolean true
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1699 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Device1"
   array [
      dict entry(
         string "UUIDs"
         variant             array [
               string "00001800-0000-1000-8000-00805f9b34fb"
               string "00001801-0000-1000-8000-00805f9b34fb"
               string "0000180f-0000-1000-8000-00805f9b34fb"
            ]
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1700 path=/; interface=org.freedesktop.DBus.ObjectManager; member=InterfacesAdded
   object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9/service0001"
   array [
      dict entry(
         string "org.freedesktop.DBus.Introspectable"
         array [
         ]
      )
      dict entry(
         string "org.bluez.GattService1"
         array [
            dict entry(
               string "UUID"
               variant                   string "00001801-0000-1000-8000-00805f9b34fb"
            )
            dict entry(
               string "Device"
               variant                   object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9"
            )
            dict entry(
               string "Primary"
               variant                   boolean true
            )
            dict entry(
               string "Characteristics"
               variant                   array [
                  ]
            )
         ]
      )
      dict entry(
         string "org.freedesktop.DBus.Properties"
         array [
         ]
      )
   ]
signal sender=:1.20 -> dest=(null destination) serial=1701 path=/; interface=org.freedesktop.DBus.ObjectManager; member=InterfacesAdded
   object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9/service0001/char0002"
   array [
      dict entry(
         string "org.freedesktop.DBus.Introspectable"
         array [
         ]
      )
      dict entry(
         string "org.bluez.GattCharacteristic1"
         array [
            dict entry(
               string "UUID"
               variant                   string "00002a05-0000-1000-8000-00805f9b34fb"
            )
            dict entry(
               string "Service"
               variant                   object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9/service0001"
            )
            dict entry(
               string "Notifying"
               variant                   boolean false
            )
            dict entry(
               string "Flags"
               variant                   array [
                     string "indicate"
                  ]
            )
            dict entry(
               string "Descriptors"
               variant                   array [
                  ]
            )
         ]
      )
      dict entry(
         string "org.freedesktop.DBus.Properties"
         array [
         ]
      )
   ]
signal sender=:1.20 -> dest=(null destination) serial=1702 path=/; interface=org.freedesktop.DBus.ObjectManager; member=InterfacesAdded
   object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9/service0028"
   array [
      dict entry(
         string "org.freedesktop.DBus.Introspectable"
         array [
         ]
      )
      dict entry(
         string "org.bluez.GattService1"
         array [
            dict entry(
               string "UUID"
               variant                   string "0000180f-0000-1000-8000-00805f9b34fb"
            )
            dict entry(
               string "Device"
               variant                   object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9"
            )
            dict entry(
               string "Primary"
               variant                   boolean true
            )
            dict entry(
               string "Characteristics"
               variant                   array [
                  ]
            )
         ]
      )
      dict entry(
         string "org.freedesktop.DBus.Properties"
         array [
         ]
      )
   ]
signal sender=:1.20 -> dest=(null destination) serial=1703 path=/; interface=org.freedesktop.DBus.ObjectManager; member=InterfacesAdded
   object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9/service0028/char0029"
   array [
      dict entry(
         string "org.freedesktop.DBus.Introspectable"
         array [
         ]
      )
      dict entry(
         string "org.bluez.GattCharacteristic1"
         array [
            dict entry(
               string "UUID"
               variant                   string "00002a19-0000-1000-8000-00805f9b34fb"
            )
            dict entry(
               string "Service"
               variant                   object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9/service0028"
            )
            dict entry(
               string "Notifying"
               variant                   boolean false
            )
            dict entry(
               string "Flags"
               variant                   array [
                     string "read"
                     string "notify"
                  ]
            )
            dict entry(
               string "Descriptors"
               variant                   array [
                  ]
            )
         ]
      )
      dict entry(
         string "org.freedesktop.DBus.Properties"
         array [
         ]
      )
   ]
signal sender=:1.20 -> dest=(null destination) serial=1704 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9/service0001; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.GattService1"
   array [
      dict entry(
         string "Characteristics"
         variant             array [
               object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9/service0001/char0002"
            ]
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1705 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9/service0028; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.GattService1"
   array [
      dict entry(
         string "Characteristics"
         variant             array [
               object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9/service0028/char0029"
            ]
      )
   ]
   array [
   ]
signal sender=:1.20 -> dest=(null destination) serial=1706 path=/org/bluez/hci0/dev_70_70_B2_BD_79_C9; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.bluez.Device1"
   array [
      dict entry(
         string "GattServices"
         variant             array [
               object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9/service0001"
               object path "/org/bluez/hci0/dev_70_70_B2_BD_79_C9/service0028"
            ]
      )
   ]
   array [
   ]

For info, I can still reproduce this issue with 
Google Chrome	52.0.2717.5 (Official Build) dev (64-bit)

Logs are below:

[8906:8906:0512/125140:VERBOSE1:bluetooth_dispatcher_host.cc(940)] requestDevice called with the following filters: 
[8906:8906:0512/125140:VERBOSE1:bluetooth_dispatcher_host.cc(942)] Name: 
[8906:8906:0512/125140:VERBOSE1:bluetooth_dispatcher_host.cc(943)] Name Prefix: 
[8906:8906:0512/125140:VERBOSE1:bluetooth_dispatcher_host.cc(944)] Services:
[8906:8906:0512/125140:VERBOSE1:bluetooth_dispatcher_host.cc(945)] 	[
[8906:8906:0512/125140:VERBOSE1:bluetooth_dispatcher_host.cc(947)] 		0000180f-0000-1000-8000-00805f9b34fb
[8906:8906:0512/125140:VERBOSE1:bluetooth_dispatcher_host.cc(948)] 	]
[8906:8906:0512/125140:VERBOSE1:bluetooth_dispatcher_host.cc(951)] requestDevice called with the following optional services: 
[8906:8906:0512/125140:VERBOSE1:bluetooth_dispatcher_host.cc(1078)] Populating 1 devices in chooser 1
[8906:8906:0512/125140:VERBOSE1:bluetooth_dispatcher_host.cc(1081)] 	AC:E6:4B:05:88:2D
[8906:8906:0512/125140:VERBOSE1:bluetooth_adapter_bluez.cc(1139)] AddDiscoverySession
[8906:8906:0512/125140:VERBOSE1:bluetooth_adapter_bluez.cc(1435)] OnSetDiscoveryFilter
[8906:8906:0512/125140:VERBOSE1:bluetooth_adapter_bluez.cc(1320)] OnStartDiscovery
[8906:8906:0512/125140:VERBOSE1:bluetooth_adapter.cc(280)] BluetoothAdapter::OnStartDiscoverySession
[8906:8906:0512/125140:VERBOSE1:bluetooth_dispatcher_host.cc(1103)] Started discovery session for 1
[8906:8906:0512/125141:VERBOSE1:bluetooth_adapter_bluez.cc(943)] Discovering changed: 1
[8906:8906:0512/125141:WARNING:arc_bluetooth_bridge.cc(683)] no Bluetooth instance available
[8906:8906:0512/125141:VERBOSE1:bluetooth_dispatcher_host.cc(561)] Adding device to all choosers: 71:88:0A:BF:CE:ED
[8906:8906:0512/125141:WARNING:arc_bluetooth_bridge.cc(683)] no Bluetooth instance available
[8906:8906:0512/125141:VERBOSE1:bluetooth_dispatcher_host.cc(561)] Adding device to all choosers: CD:36:32:47:CA:1C
[8906:8906:0512/125142:VERBOSE1:bluetooth_allowed_devices_map.cc(47)] Adding a device to Map of Allowed Devices.
[8906:8906:0512/125142:VERBOSE1:bluetooth_allowed_devices_map.cc(72)] Id generated for device: z6jI7OjNfTo1O/gDSujvkw==
[8906:8906:0512/125142:VERBOSE1:bluetooth_dispatcher_host.cc(1223)] Device: Nexus 5X
[8906:8906:0512/125142:VERBOSE1:bluetooth_dispatcher_host.cc(1224)] UUIDs: 
[8906:8906:0512/125142:VERBOSE1:bluetooth_dispatcher_host.cc(1230)] 	 Allowed: 0000180f-0000-1000-8000-00805f9b34fb
[8906:8906:0512/125142:VERBOSE1:bluetooth_discovery_session.cc(45)] Stopping device discovery session.
[8906:8906:0512/125142:VERBOSE1:bluetooth_adapter_bluez.cc(1202)] RemoveDiscoverySession
[8906:8906:0512/125142:VERBOSE1:bluetooth_adapter_bluez.cc(1367)] OnStopDiscovery
[8906:8906:0512/125142:VERBOSE1:bluetooth_device_bluez.cc(373)] /org/bluez/hci0/dev_71_88_0A_BF_CE_ED: Connecting, 1 in progress
[8906:8906:0512/125142:VERBOSE1:bluetooth_device_bluez.cc(618)] /org/bluez/hci0/dev_71_88_0A_BF_CE_ED: Connecting
[8906:8906:0512/125142:VERBOSE1:bluetooth_adapter_bluez.cc(943)] Discovering changed: 0
[8906:8906:0512/125142:VERBOSE1:bluetooth_event_router.cc(221)] Releasing Adapter.
[8906:8906:0512/125143:VERBOSE1:bluetooth_device_bluez.cc(634)] /org/bluez/hci0/dev_71_88_0A_BF_CE_ED: Connected, 0 still in progress
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_service_client.cc(115)] Remote GATT service property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0001: UUID
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_service_client.cc(115)] Remote GATT service property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0001: Device
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_service_client.cc(115)] Remote GATT service property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0001: Primary
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_service_client.cc(85)] Remote GATT service added: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0001
[8906:8906:0512/125145:VERBOSE2:bluetooth_device_bluez.cc(555)] Remote GATT service does not belong to this device.
[8906:8906:0512/125145:VERBOSE1:bluetooth_device_bluez.cc(559)] Adding new remote GATT service for device: 71:88:0A:BF:CE:ED
[8906:8906:0512/125145:VERBOSE1:bluetooth_remote_gatt_service_bluez.cc(28)] Creating remote GATT service with identifier: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0001
[8906:8906:0512/125145:VERBOSE2:bluetooth_device_bluez.cc(555)] Remote GATT service does not belong to this device.
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_characteristic_client.cc(233)] Remote GATT characteristic property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0001/char0002: UUID
[8906:8906:0512/125145:VERBOSE3:bluetooth_remote_gatt_service_bluez.cc(241)] Properties of unknown characteristic changed
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_characteristic_client.cc(233)] Remote GATT characteristic property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0001/char0002: Service
[8906:8906:0512/125145:VERBOSE3:bluetooth_remote_gatt_service_bluez.cc(241)] Properties of unknown characteristic changed
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_characteristic_client.cc(233)] Remote GATT characteristic property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0001/char0002: Notifying
[8906:8906:0512/125145:VERBOSE3:bluetooth_remote_gatt_service_bluez.cc(241)] Properties of unknown characteristic changed
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_characteristic_client.cc(233)] Remote GATT characteristic property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0001/char0002: Flags
[8906:8906:0512/125145:VERBOSE3:bluetooth_remote_gatt_service_bluez.cc(241)] Properties of unknown characteristic changed
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_characteristic_client.cc(202)] Remote GATT characteristic added: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0001/char0002
[8906:8906:0512/125145:VERBOSE1:bluetooth_remote_gatt_service_bluez.cc(202)] Adding new remote GATT characteristic for GATT service: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0001, UUID: 00001801-0000-1000-8000-00805f9b34fb
[8906:8906:0512/125145:VERBOSE1:bluetooth_remote_gatt_characteristic_bluez.cc(50)] Creating remote GATT characteristic with identifier: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0001/char0002, UUID: 00002a05-0000-1000-8000-00805f9b34fb
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_service_client.cc(115)] Remote GATT service property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0028: UUID
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_service_client.cc(115)] Remote GATT service property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0028: Device
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_service_client.cc(115)] Remote GATT service property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0028: Primary
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_service_client.cc(85)] Remote GATT service added: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0028
[8906:8906:0512/125145:VERBOSE2:bluetooth_device_bluez.cc(555)] Remote GATT service does not belong to this device.
[8906:8906:0512/125145:VERBOSE1:bluetooth_device_bluez.cc(559)] Adding new remote GATT service for device: 71:88:0A:BF:CE:ED
[8906:8906:0512/125145:VERBOSE1:bluetooth_remote_gatt_service_bluez.cc(28)] Creating remote GATT service with identifier: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0028
[8906:8906:0512/125145:VERBOSE2:bluetooth_remote_gatt_service_bluez.cc(198)] Remote GATT characteristic does not belong to this service.
[8906:8906:0512/125145:VERBOSE2:bluetooth_device_bluez.cc(555)] Remote GATT service does not belong to this device.
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_characteristic_client.cc(233)] Remote GATT characteristic property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0028/char0029: UUID
[8906:8906:0512/125145:VERBOSE3:bluetooth_remote_gatt_service_bluez.cc(241)] Properties of unknown characteristic changed
[8906:8906:0512/125145:VERBOSE3:bluetooth_remote_gatt_service_bluez.cc(241)] Properties of unknown characteristic changed
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_characteristic_client.cc(233)] Remote GATT characteristic property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0028/char0029: Service
[8906:8906:0512/125145:VERBOSE3:bluetooth_remote_gatt_service_bluez.cc(241)] Properties of unknown characteristic changed
[8906:8906:0512/125145:VERBOSE3:bluetooth_remote_gatt_service_bluez.cc(241)] Properties of unknown characteristic changed
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_characteristic_client.cc(233)] Remote GATT characteristic property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0028/char0029: Notifying
[8906:8906:0512/125145:VERBOSE3:bluetooth_remote_gatt_service_bluez.cc(241)] Properties of unknown characteristic changed
[8906:8906:0512/125145:VERBOSE3:bluetooth_remote_gatt_service_bluez.cc(241)] Properties of unknown characteristic changed
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_characteristic_client.cc(233)] Remote GATT characteristic property changed: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0028/char0029: Flags
[8906:8906:0512/125145:VERBOSE3:bluetooth_remote_gatt_service_bluez.cc(241)] Properties of unknown characteristic changed
[8906:8906:0512/125145:VERBOSE3:bluetooth_remote_gatt_service_bluez.cc(241)] Properties of unknown characteristic changed
[8906:8906:0512/125145:VERBOSE2:bluetooth_gatt_characteristic_client.cc(202)] Remote GATT characteristic added: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0028/char0029
[8906:8906:0512/125145:VERBOSE2:bluetooth_remote_gatt_service_bluez.cc(198)] Remote GATT characteristic does not belong to this service.
[8906:8906:0512/125145:VERBOSE1:bluetooth_remote_gatt_service_bluez.cc(202)] Adding new remote GATT characteristic for GATT service: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0028, UUID: 0000180f-0000-1000-8000-00805f9b34fb
[8906:8906:0512/125145:VERBOSE1:bluetooth_remote_gatt_characteristic_bluez.cc(50)] Creating remote GATT characteristic with identifier: /org/bluez/hci0/dev_71_88_0A_BF_CE_ED/service0028/char0029, UUID: 00002a19-0000-1000-8000-00805f9b34fb

@rkc, could this be related to https://bugs.chromium.org/p/chromium/issues/detail?id=604166?

I think this is WAI. When a service gets created it adds itself to the list of observers for the BluetoothGattServiceClient and BluetoothGattCharacteristicClient. These two clients notify *all* observers of any services or characteristics added. The logs are a bit spammy, but then again they are VLOG(3).

I'm not sure to get it.
What are *all* the observers there? 

In the bluez implementation there are clients that are actively listening for changes in the corresponding Bluez objects. For example the BluetoothGattCharacteristicClient is listening for changes in *any* characteristics, same thing with the BluetoothGattServiceClient. When these clients receive an event from bluez they notify its observers of this change.

When a BluetoothRemoteGattServiceBluez object is created, it adds itself as an observer of BluetoothGattCharacteristicClient, meaning it will be notified of changes to *any* characteristics.

Imagine there as a device with two services A and B. Service A contains characteristic C and service B contains characteristic D. When "D" changes services "A" and "B" will be notified of a change in a characteristic. "A" will notice that "D" is not in "A" and log "Properties of unknown characteristic changed". "B" will notice that "D" is in "B" process the event.