When searching for objects, we naively traversed through type parameter
constraints. This leads to infinite recursion when there are cycles
through type parameter constraints.

Break these cycles by tracking type parameter names that have previously
been encountered. This ensures we walk type parameter constraints at
most once. Note that if the desired object was not found on the first
search of the constraint, there is no need to search again.

Note: this cherry-pick also adjusts a test error message to match
go1.18.

Updates golang/go#51727

Change-Id: Ifcdf4b138a0e95441e485bbb9ee21c01b04eaed4
Reviewed-on: https://go-review.googlesource.com/c/tools/+/393376
Trust: Robert Findley <rfindley@google.com>
Run-TryBot: Robert Findley <rfindley@google.com>
gopls-CI: kokoro <noreply+kokoro@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
(cherry picked from commit d67eab4)
Reviewed-on: https://go-review.googlesource.com/c/tools/+/393635
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

Update x/tools from internal-branch.go1.18-vendor to pick up the
cherry-picked fix for #51727.

The following commands were used, from the cmd module:
  go get -d golang.org/x/tools@internal-branch.go1.18-vendor
  go mod tidy
  go mod vendor

Fixes #51727

Change-Id: I380a66fee585c8c12f9646de87ffb5e398b4ba80
Reviewed-on: https://go-review.googlesource.com/c/go/+/397476
Trust: Robert Findley <rfindley@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>