[1.6>1.7] [MERGE #3338 @MikeHolman] assert that function we are JITing has a body
[1.6>1.7] [MERGE #3338 @MikeHolman] assert that function we are JITing has a body

Merge pull request #3338 from MikeHolman:assertbody

There was a bug that caused this not to happen, and it hit null AV on JIT process. This assert should allow us to catch such an issue earlier, when we have more context.

OS: 12457116

Microsoft/ChakraCore,mrkmarron/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,mrkmarron/ChakraCore