There are several classes that have inner classes not declared with the
'static' modifier. For these classes Findbugs reports:
This class is an inner class, but does not use its embedded reference
to the object which created it. This reference makes the instances of
the class larger, and may keep the reference to the creator object alive
longer than necessary. If possible, the class should be made static.
Add a 'static' modifier on these classes.
Change-Id: I0244bb1cd5662398f79c61d442df815e3811bf12