Setting a header or footer should cause a relayout
https://bugs.webkit.org/show_bug.cgi?id=114070

Reviewed by Sam Weinig.

Mark the RenderView as needing layout in order to adjust everything for the new 
header/footer.

* page/FrameView.cpp:
(WebCore::FrameView::setHeaderHeight):
(WebCore::FrameView::setFooterHeight):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@147806 268f45cc-cd09-0410-ab3c-d52691b4dbfc