Avoid creating APEX variant for sdk member

Previously, an APEX variant was created for a module that was a member
of an SDK just in case it had to be replaced with an APEX requested
snapshotted version of that member. That was necessary because that was
the only way to have APEX specific replacements.

Since then a new method called ReplaceDependenciesIf() has been added
which provides fine grained control over which dependencies are
replaced. This change uses that new method to handle the replacements
which allows the APEX variants to be removed.

Bug: 161928524
Test: m nothing
Change-Id: If3869dd6753dc182b099af566b20fbc9c9c6eff7