client: inline helpers for getting/setting client geometry
Adding some inline helpers for getting/setting client geometry as GdkRectangle or XWindowChanges structs. Since they're inline, the generated code won't be bigger/slower than it was.
This not just cleans up the code, but also serves as a preparational step for further code compactions as well as more sophisticated things like caching geometry, etc.
Signed-off-by: Enrico Weigelt, metux IT consult info@metux.net