Tests that are consitently failing:

BluetoothTestWinrtOnly.GattServices_ObserversCalls/0
BluetoothTestWinrt.GetPrimaryServices/1
BluetoothRemoteGattServiceTestWinrt.SimulateGattServiceRemove/1
BluetoothTestWinrt.GetPrimaryServicesByUUID/1
BluetoothTestWinrtOnly.BluetoothGattConnection_DisconnectGatt_Cleanup/0
BluetoothTestWinrt.GetGattServices_and_GetGattService/1
BluetoothRemoteGattServiceTestWinrt.GetCharacteristicsByUUID/1
BluetoothTestWinrtOnly.GattServicesDiscovered_Success/0

Sample builds:
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Win10%20Tests%20x64%20%28dbg%29/2245
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Win10%20Tests%20x64%20%28dbg%29/2242
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Win10%20Tests%20x64%20%28dbg%29/2240
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Win10%20Tests%20x64%20%28dbg%29/2236

Reverting a suspected CL crrev.com/c/1156703 didn't fix them.