Revert "Bug 558642: SafeRunner can return results"

This reverts commit 30247bf8acddfc1a8b89127aeb1caf66dad8ecf8.

Reason for revert: regressions in jface.text.tests and
core.tests.runtime.tests

Change-Id: Ibc3f827cb7dabb1f5c0b24b9d4636ee6782e3da3
Signed-off-by: Lars Vogel <Lars.Vogel@vogella.com>
3 files changed