Created attachment 430708 [details, diff] Patch to fix the issue Sets @kdebase-runtime-4.14 and @kdelibs-4.14 contain incorrect packages. khelpcenter and baloo-widgets are now in kde-apps category.
Thanks. https://gitweb.gentoo.org/proj/kde.git/commit/?id=d54a1d1c3a3e52a5e9922e9bdc224f901e5bfe7c