Fixes following test failures :
 ProtoFFITests.CSFFITest.TestListMarshalling_DStoCS
 ProtoFFITests.CSFFITest.TestListMarshalling_DStoCS_CStoDS
and defect:
 http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-2301
Merge pull request #1305 from sharadkjaiswal/MAGN-2301

Fixes following test failures :