Remove Vector::dataSlot(), it has no implementation
https://bugs.webkit.org/show_bug.cgi?id=109999

Patch by Benjamin Poulain <bpoulain@apple.com> on 2013-02-18
Reviewed by Andreas Kling.

VectorBufferBase does not implement any function bufferSlot().
The file only compiles because that part of the template is never
instantiated.

* wtf/Vector.h:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@143254 268f45cc-cd09-0410-ab3c-d52691b4dbfc