computeOrigin      62 Source/web/ViewportAnchor.h     WebCore::IntPoint computeOrigin(const WebCore::IntSize& currentViewSize) const;
computeOrigin    1598 Source/web/WebViewImpl.cpp                 IntPoint scrollOffsetAtNewScale = viewportAnchor.computeOrigin(viewportSize);
computeOrigin    1601 Source/web/WebViewImpl.cpp                 IntPoint scrollOffsetAtNewScale = clampOffsetAtScale(viewportAnchor.computeOrigin(viewportSize), pageScaleFactor());