Second attempt to fix the Windows bot

Unreviewed.

* JavaScriptCore.vcproj/JavaScriptCore/JavaScriptCoreExports.def:
* JavaScriptCore.vcxproj/JavaScriptCoreExportGenerator/JavaScriptCoreExports.def.in:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@147828 268f45cc-cd09-0410-ab3c-d52691b4dbfc