[EFL][WK2] Remove dead code after r142169
https://bugs.webkit.org/show_bug.cgi?id=109251

Reviewed by Benjamin Poulain.

* WebProcess/WebCoreSupport/WebChromeClient.cpp:
(WebKit::WebChromeClient::contentsSizeChanged):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@142222 268f45cc-cd09-0410-ab3c-d52691b4dbfc