ve.test: Import K-JS test suite for object utilities

We've housed these utilities for a while and changed some of
them quite a bit. Importing them to avoid regressions and
ensure we keep them in sync with our fork of it.

Removed references back through `@source`. They are sufficiently
different that the reference no longer adds any value.

Imported from https://github.com/Krinkle/K-js/blob/v0.1.2/test/K.test.js.

Change-Id: I9e71297246b7c248c1f032ba6b6ae1123519f3c1
Merge "ve.test: Import K-JS test suite for object utilities"