Use WTF::Optional for ScrollView's m_deferredScrollDelta / m_deferredScrollOffsets instead of std::unique_ptr as it is more suited for this purpose.
Created attachment 279036 [details] Patch
Comment on attachment 279036 [details] Patch Clearing flags on attachment: 279036 Committed r200963: <http://trac.webkit.org/changeset/200963>
All reviewed patches have been landed. Closing bug.