[Ohrrpgce] SVN: teeemcee/9453 Make Surface width and height signed rather than unsigned ints, to match

[subversion at HamsterRepublic.com]

teeemcee
2017-09-24 22:44:27 -0700 (Sun, 24 Sep 2017)
255
Make Surface width and height signed rather than unsigned ints, to match Frame, avoid bugs, and simplify code

It turns out that the width and height were declared as signed in the FB headers
anyway. See, bugs. Best to only use unsigned ints for bitmasks.
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U   wip/surface.cpp
U   wip/surface.h