scala/scala — pull request #1768 by paulp (2012-12-13 04:10:20+00:00)
Title: Eliminating var-like setter tpe_= on Tree.

Deprecated tpe_= on Tree, which is redundant with and
less useful than setType. To provide a small layer of
insulation from the direct nulling out of mutable fields
used to signal the typer, added def clearType() which is
merely tree.tpe = null but is shamefaced about the null
and var-settings parts like a respectable method should be.