Due to the increased accuracy of line counting and registering, when a

Due to the increased accuracy of line counting and registering, when a
latex error occurs inside a table, the exact faulty table row is spotted.
However, if all cells of a table row are output on the same line, lyx is
not able to tell what cell caused the error and highlights the last cell
of the row. This patch allows to output each cell of a table on its own
line, such that the exact point where the error occurred can be highlighted.
Note that this is only done when exporting for preview, and in normal (nice)
exports everything goes as usual.

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@37643 a592a061-630c-0410-9148-cb99ea01b6c8