It seems the pagination is done in PrintContext::computePageRects in WebCore/page/PrintContext is responsible for pagination on Chromium (note that this function is used in WebKit/chromium/src/WebFrameImpl.cpp via ChromePrintContext, which is a subclass of PrintContext). So, WebCore::computePageRectsForFrame in WebCore/page/FrameChromium.cpp, which is almost as same as PrintContext::computePageRects, would be unnecessary.
Created attachment 46981 [details]
Comment on attachment 46981 [details]
Clearing flags on attachment: 46981
Committed r53527: <http://trac.webkit.org/changeset/53527>
All reviewed patches have been landed. Closing bug.