CompatibilityParts if compatibility parts are also being closed.

Previously if there were CompatibilityPart elements which were dirtied,
the dirtied nonCompatibilityParts were just ignored. So now This has
been fixed so that a single dialog pops up to save the dirtied
nonCompatibility part resources and dirtied CompatilityPart resources.

Also added tests to test the new API added in SaveablesList.

Change-Id: I0c6b498dca49b574eaa6fab3f1af73c03ffb0fc3