The basic `FindAllAsync()` method returns a collection of `DeviceInformation` objects representing all device interfaces on the system. This MR adds a basic implementation of this method, and the associated `IDeviceInformation` and `DeviceInformationCollection` objects it returns. For `IDeviceInformation`, this MR only implements the `Id()` method, which returns the symbolic link for the registered interface.
A basic working `DeviceInformation` and `FindAll` implementations are needed to implement `DeviceWatcher`'s `Added`, `Removed` events, which in turn is required for basic device discovery in `Windows.Devices.Bluetooth`.
-- v5: windows.devices.enumeration: Create IDeviceInformation objects from all present device interfaces. windows.devices.enumeration: Add a stubbed IDeviceInformation implementation for device interfaces. windows.devices.enumeration: Add a stubbed implementation for FindAllAsync() and DeviceInformationCollection. windows.devices.enumeration/tests: Add conformance tests for FindAllAsync().