most of length in vcl are calculated in 'long'
but array of X position tend to be in sal_Int32.
As a prep work to be able to support 'double'
as the base type of Device Coordinate, harmonize
the use of 'long' for non-float coordinate.

Change-Id: I7cb33301ff6a5e2c62247b36a4e07e168a58a323