It can do that too, among other things. While I have read a bit about it in the past I have not actually used it so far. The closest analogue in a nutshell is probably "something like Windows GDI" independent of any OS. That includes different output devices (a simple memory bitmap, a PDF, an OpenGL texture which was created by rendering into a framebuffer, ...).
EAWebkit uses cairo interally to render the webpages/uis you load with it out to a bitmap you can use for your rendering pipe.