[GTK] [gyp] Expose a few more compiler defines for the gyp build
https://bugs.webkit.org/show_bug.cgi?id=113109

Reviewed by Gustavo Noronha Silva.

* gyp/Configuration.gypi.in: Expose the version number string and data
directory to the gyp build as command-line arguments.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@146676 268f45cc-cd09-0410-ab3c-d52691b4dbfc