This allows us to ignore all the delays when the device is emulated, with the
idea being to do dozens of device emulations in the CI tests.
Also, do not call fu_progress_sleep() when the device is emulated.
Now incorporate is fixed to copy across the properties we need in the
superclass, we don't need to do the subclass ->probe().
Note, we still need to do the subclassed ->probe() when using
FU_UDEV_DEVICE_FLAG_VENDOR_FROM_PARENT or when looking at properties
on the parent device.
This also removes the spurious 'already set GType to FuVliUsbhubDevice,
ignoring FuVliUsbhubDevice' messages when running the daemon.
It's actually quite hard to build a front-end for fwupd at the moment
as you're never sure when the progress bar is going to zip back to 0%
and start all over again. Some plugins go 0..100% for write, others
go 0..100% for erase, then again for write, then *again* for verify.
By creating a helper object we can easily split up the progress of the
specific task, e.g. write_firmware().
We can encode at the plugin level "the erase takes 50% of the time, the
write takes 40% and the read takes 10%". This means we can have a
progressbar which goes up just once at a consistent speed.
This allows a device subclass to call the parent method after doing an initial
action, or even deliberately not call the *generic* parent method at all.
It also simplifies the plugins; you no longer have to remember what the plugin
is deriving from and accidentally clobber the wrong superclass method.