Remove unneed null checks

Remove unneed null checks

A recent JDT update seems to have extended the null flow analysis
to consider the case where assigning an Integer from an int makes
it effectively non-null.

This points out that we were doing some redundant null checks.

Change-Id: Ie222b519f02e45584ae4f47381025fd28a8f6423
Signed-off-by: Alexandre Montplaisir <alexmonthy@voxpopuli.im>
Reviewed-on: https://git.eclipse.org/r/46967
Reviewed-by: Hudson CI