Internally and in the network protocol (for the new version) we
now store the actual number of segments rather than the size of the
full segments array in bytes. This change consists of multiple changes
to handle this:
* Make the qxl parser calculate num_segments
* Make the canvas stroke code handle the new SpicePath layout.
* Fix up is_equal_path in red_worker.c for the new layout
* replace multiple calls to spice_marshall_PathSegment with a single
spice_marshall_Path call
* Make the byte_size() array size handling do the conversion from
network size to number of elements when marshalling/demarshalling.
* Update the current spice protocol to send the segment count rather than
the size
* Update the old spice protocol to use the new byte_size functionallity
to calculate the size sent and the number of elements recieved
A @c_ptr pointer is stored in memory as a real pointer rather than a
SPICE_ADDRESS. This is a temporary thing that will be removed again
when all SPICE_ADDRESSes have been converted to real pointer.
This means the member is not sent on the network at all.
Instead its initialized to the attribute argument when demarshalled.
This is useful for backwards compatibility support.
This is required because we don't want to free messages that just
refer to the unparsed message (like SpiceMsgData).
Also, in the future we might need it for more complex demarshalling.
The "spice.proto" file describes in detail the networking prototcol
that spice uses and spice_codegen.py can parse this and generate
demarshallers for such network messages.