scala/scala — pull request #1654 by xeno-by (2012-11-21 08:49:03+00:00)
Title: SI-6696 removes "helper" tree factory methods

As experience shows, these methods can easily be a source of confusion
for the newcomers: https://issues.scala-lang.org/browse/SI-6696.

I'm only leaving the `TypeTree(tp)` factory, since the facility to
set underlying types for type trees is not exposed in the public API,
as it's inherently mutable.