In an effort to tackle the affordable housing crisis, Oregon could end single-family zoning this legislative session.   Oregon would be the first state to do so if lawmakers who support the idea succeed.  Willamette Week reports Oregon House Speaker Tina Kotek is drafting legislation that requires cities with more than 10,000 residents to allow up to four homes to be built on parcels currently zoned exclusively for single-family housing.  1000 Friends of Oregon deputy director Mary Kyle McCurdy says such a proposal could meet the needs of more Oregon families in the places where affordability is an issue.  In December, Minneapolis became the first major city to eliminate single-family zoning.  Portland is considering a similar plan.  The city has the fourth-highest percentage of single-family home occupancy in the nation.