This reverts commit b690cb67be9b487eb10156c03e2c00869e88cc9d, reversing
changes made to 50dd431dffe5cf86e9064a652d6b01dbbe542cf0. This is
necessary because the reverted changeset reduced coverage by an unknown
extent.
The harness file `Test262Error.js` has not contained executable code since it
was introduced in this project [1]. The definition of the `Test262Error`
function has consistently been located in the `sta.js` harness file which test
runners are expected to inject into the test environment.
Remove the file and all references to it.
[1] See commit c33bf0e0439e6f6bf084c1524d7df8d2b41c515d
