Depending on levels of funding, depending on the final plan, transit on the Route 7 corridor from Tysons Corner to Old Town Alexandria could be functioning any time from 10 to 20 years from now, officials of the Northern Virginia Transportation Commission told a joint work session of the F.C. City Council and Planning Commission Tuesday night. The issue for the Falls Church stretch includes whether or not local officials would want the line – light rail, bus rapid transit or street car – to divert to stop at the East Falls Church Metro station or not. There was no initial consensus on that point at Tuesday’s meeting.