Xdebug configuration with no path maps causes NPE.

[g4wjs]

Xdebug requires a path map to be set, unfortunately if web server and PHPEclipse are on same machine it is not at all clear that a path map is required.

With no path maps an NPE is thrown silently and source trace fails to work which means breakpoints are not reflected in the UI even though the script execution halts.

I would suggest that not having any path map should use a default of mapping the source to the path supplied from the Xdebug client supplied by the PHP engine.

[incastrix]

Closed in changeset #1639.