For errors, it just printed "Failure: expected <Error()> found
<Error()>" and completely omitted the specific error type and the
message.

The new output is:
Failure:
expected:
Error(Error: my explicit error)
found:
Error(ReferenceError: ffi is not defined)

R=mstarzinger@chromium.org

Change-Id: Ie17a97e4413c4585b9560fd1c408018ee8c06701
Reviewed-on: https://chromium-review.googlesource.com/1092746Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53625}