Replace Boolean wrapper object by boolean primitive type when an object
is not necessary:
 - The variable must be not null,
 - The result should not make more autoboxing/unboxing than the original
code.

Given:
        Boolean shouldBeAPrimitiveBoolean = Boolean.TRUE;
        aBoolean &= shouldBeAPrimitiveBoolean;
        anotherBoolean |= shouldBeAPrimitiveBoolean;
        yetAnotherBoolean ^= shouldBeAPrimitiveBoolean;

When:
Applying "Primitive rather than wrapper" clean up...

Then:
        boolean shouldBeAPrimitiveBoolean = Boolean.TRUE;
        aBoolean &= shouldBeAPrimitiveBoolean;
        anotherBoolean |= shouldBeAPrimitiveBoolean;
        yetAnotherBoolean ^= shouldBeAPrimitiveBoolean;

Also merge code

Change-Id: I418f5d0cffcd165c7fed7497516101546f6ad63f
Signed-off-by: Fabrice Tiercelin <fabrice.tiercelin@yahoo.fr>
Reviewed-on: https://git.eclipse.org/r/c/jdt/eclipse.jdt.ui/+/179803
Reviewed-by: Jörg Kubitz <jkubitz-eclipse@gmx.de>
Tested-by: JDT Bot <jdt-bot@eclipse.org>