VS2010 WebCoreGenerated build scripts should use new feature-defines script.
Update FEATURE_DEFINES string generation for VS2010 solution.
https://bugs.webkit.org/show_bug.cgi?id=113737.

Reviewed by Timothy Horton.

* WebCore.vcxproj/build-generated-files.sh:
* win/tools/scripts/feature-defines2010.sh: Added.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@147375 268f45cc-cd09-0410-ab3c-d52691b4dbfc