scala/scala — pull request #1789 by paulp (2012-12-19 19:16:07+00:00)
Title: SI-6846, regression in type constructor inference.

In 658ba1b4e6 some inference was gained and some was lost.
In this commit we regain what was lost and gain even more.
Dealiasing and widening should be fully handled now, as
illustrated by the test case.