Separate versioned/unversioned testing in sdk/cc_sdk_test.go

Uses new capability added in previous change to separate the testing of
the versioned and unversioned snapshots in sdk/cc_sdk_test.go. Any test
that generated an _snapshot module that simply listed the modules and
did not check a new type only tests the unversioned output to reduce
the duplication and cost of changing the tests.

Bug: 180479010
Test: m nothing
Change-Id: If11f82b3dd8ec79110b3a2f5adf193b6464000ab