go/internal/gccgoimporter: remove guard on some assertions
Remove unnecessary conditional guard for a couple of assertions in the
type parser's update() method (inspired by comment from Robert). No
change in functionality.
Change-Id: I706a54569e75c6960768247889b7dec3f267dde9
Reviewed-on: https://go-review.googlesource.com/c/go/+/194565
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Robert Griesemer <gri@golang.org>