Loosen the definition of "lossless" a bit so that we can use high
quality JPEG to refresh damaged parts of the screen. Although this
isn't bit perfect, it is close enough that most users will not be
able to tell the difference.

Level 9 is used rather than level 8 because some monitors have
exaggerated contrast that allows the artefacts from level 8 to be
noticeable.

Most encoders don't have a palette mode, so don't force them to
specify a dummy value to the Encoder base class constructor.

If we have plenty of bandwidth then CPU might be the limiting resource.
Unfortunately we don't have a good number for that limit, so add a
conservative hard coded value.

If we're out of time then we will definitely overshoot, so don't even
try.

The update size is in bytes, but we are counting pixels. So make
sure we convert things properly before comparing.

If an area recently changed then we can guess that it will most likely
change again very soon. In such a case it is meaningless to send a
lossless refresh as it will directly be overwritten. Keep track of
such areas and avoid refreshing them until we no longer see any
changes to them.

The reference for "dueTime" wasn't properly updated when this code
was refactored from a static method to a normal object method.

The API and ABI isn't as stable as we need, so it isn't safe to
link it dynamically even on Linux.

We cannot assume endian-ness for the cursor we get from XFixes.
Adjust the algorithm to properly follow the specification.

We get a whole bunch of very tiny areas, which is very inefficient to
deal with. Instead create a rectangle around every "list" of connected
glyphs (usually each line).

The compiler isn't smart enough to figure all of these out, so
restructure things a bit to avoid warnings.

We should be looking at the physical monitor layout, not the current
RFB layout. The latter might not be in sync with the local monitors.

Remnants from an earlier version of the code.

There are some cases where the server state will not automatically
be updated on a change. A prominent one is when only RFB attributes
were changes (e.g. the screen ID) but nothing else. In that case
there is no actual change in the X server, so it never sends any
notification about change back to us.

x0vncserver might only be observing part of the display, so we need
to adjust any coordinates before we give them to the RFB core.

Release queueMutex using finally blocks

Ensure queueMutex is always correctly released by using finally blocks. This is the closest approximation of AutoMutex style automatic release you can get in Java.

Makes it possible to use certificates from all popular CAs with
TigerVNC.

Makes sure it is readable in a multi screen configuration, as otherwise
it might end up crossing multiple screens.

For KDE we can sometimes get a bunch of stray FL_LEAVE events before
gaining focus. Sending their included button information gets things
in the incorrect order with regard to other synchronisation we do on
focus. So just ignore buttons as the only information we want out of
the leave information is a position update.

It can get a bit intrusive for experienced users, so try to reduce
the impact of it.

We had partial coverage for vncviewer/ already, but fix up the last
pieces.

We put the try/catch as close as possible to the writes in all
other case, so make sure this code also follows that pattern.

Setting Ctrl or Alt key on menu only sends the key press, and the
state is lost when focus is lost and recovered.
This checks the menu variable and sends the keys again if needed.

Function xorgGlxCreateVendor() is defined in glx_extinit.h, if this header is
not included, we might get either error or warning. This header also need to
be included after scrninststr.h header as it defines some structures used
in glx_extinit.h