[GTK] Expose all dependencies to the gyp build
https://bugs.webkit.org/show_bug.cgi?id=110498

Reviewed by Dirk Pranke.

* gyp/Configuration.gypi.in: Add the missing configuration cflags here.
* gyp/Dependencies.gyp: Add targets for all missing dependencies.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@143835 268f45cc-cd09-0410-ab3c-d52691b4dbfc