Extract DepIsInSameApex and RequiredSdks interfaces

The DepIsInSameApex() and RequiredSdks() methods were defined in a few
places to avoid having to depend on the whole ApexModule/SdkAware
interfaces directly. However, that has a couple of issues:
1) It duplicates functionality making it difficult to change, changes
   to the definitions outside the main interfaces do not cause compile
   time failures, instead they result in a runtime change in behavior
   which can be difficult to debug.
2) IDE navigation (specifically in Intellij) does not detect that the
   duplicate definitions can resolve to the definitions in the main
   interface.

This change extracts the methods into their own interfaces and reuses
those interfaces instead of duplicating the methods to fix both of
these issues.

Bug: 152878661
Bug: 153306490
Test: m nothing
Merged-In: I0cfdf342a14eb0bfb82b1bd17e0633d81c7facfb
Change-Id: I0cfdf342a14eb0bfb82b1bd17e0633d81c7facfb