If a bound program is relinked unsuccessfully it is supposed to keep
the executable and the program state such as the uniforms. This adds a
test for that which updates a uniform, does a failed relink and
verifies that a render succeeds with the new uniform value. This is
currently causing a use-after-free error in Mesa. The test has some
redundant allocations to try and encourage it to fail which it does
about 98% of the time.

v2: Adapt to work with GL2.0. Change the order of the colours so that
    a successful run ends with green. Delete the program after use.
Acked-by: Timothy Arceri <tarceri@itsqueeze.com>