The DEPENDS_ON macro didn't do anything and has misled many users to
think that they can write test functions that depend on other test
functions.
Task-number: QTBUG-21851
Change-Id: Ibe65b2d5d88bb81b6a0ebbe0b220f7d409a1446c
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>