scala/scala — pull request #750 by paulp (2012-06-19 16:54:36+00:00)
Title: Fix for SI-5953, extension methods crasher.

As usual, .tpe -> .tpeHK. As a side note following an old theme,
if symbols of type parameters knew that they were symbols of type
parameters, they could call tpeHK themselves rather than every call
site having to do it. It's the operation which injects dummies which
should require explicit programmer action, not the operation which
faithfully reproduces the unapplied type. Were it that way, errors could
be caught much more quickly via ill-kindedness.

Seems like an improvement over lurking compiler crashes at every call
to tparam.tpe.

Review by @adriaanm