test: wrap assert.fail when passed to callback

Currently there are many instances where assert.fail is directly passed
to a callback for error handling. Unfortunately this will swallow the
error as it is the third argument of assert.fail that sets the message
not the first.

This commit adds a new function to test/common.js that simply wraps
assert.fail and calls it with the provided message.

Tip of the hat to @trott for pointing me in the direction of this.

PR-URL: https://github.com/nodejs/node/pull/3453


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>