Add missing copyright header to ColorChooserClient.h
https://bugs.webkit.org/show_bug.cgi?id=115067

Reviewed by Andreas Kling.

* platform/ColorChooserClient.h:
This was added in 2011 by a Google employee.
http://trac.webkit.org/changeset/103168


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@149012 268f45cc-cd09-0410-ab3c-d52691b4dbfc