isMaster is not enough as long as we differ between master pointers and
keyboard. With flexible device classes, the usual checks for whether a
master device is a pointer (currently check for ->button, ->valuators or
->key) do not work as an SD may post an event through a master and mess this
check up.
Example, a device with valuators but no buttons would remove the button
class from the VCP and thus result in the
IsPointerDevice(inputInfo.pointer) == FALSE.
This will become worse in the future when new device classes are introduced
that aren't provided in the current system (e.g. a switch class).
This patch replaces isMaster with "type", one of SLAVE, MASTER_POINTER and
MASTER_KEYBOARD. All checks for dev->isMaster are replaced with an
IsMaster(dev).
Split ChangeMasterDeviceClasses into an extra XISendDeviceChangedEvent that
assembles the XI2 wire event for the DeviceChanged event. Re-use this when
detaching the last SD.
Not quite perfect yet, we still copy the device classes from the slave now
rather than from the data we had when the event occured. But it's a start.
(We can now unexport SizeDeviceInfo and CopySwapDevices, not needed anymore)
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>