set border polar with 5.2 RC1

[Christoph B. <us...@be...>]

Hi,

I'm testing a bit the new features in 5.2 RC1. I had some problems with 
`set border polar`

Consider the following script:

reset
set polar
set grid polar lw 2
unset xtics
unset ytics
set size square
unset key
# set rrange [0:6.5]
set border 0 polar
plot t lt 3 lw 2, -t lt 4 lw 2

* That one doesn't plot a polar border, only when an explicit rrange is 
set (uncomment the set rrange line).

* The polar border overlaps with the outer grid circle

* Another observation is, that the polar grid is not clipped at the 
original square border (like it is done in 5.0), but drawn until the 
canvas border.

Are those changes intended, or bugs?

Thank you,
Christoph