Unreviewed, fix build break on EFL and GTK since r173152.

* platform/graphics/cairo/GraphicsContextCairo.cpp:
(WebCore::GraphicsContext::platformInit): Remove a bool parameter because it was removed from function's declaration.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@173153 268f45cc-cd09-0410-ab3c-d52691b4dbfc