[MERGE #2067 @Cellule] WASM - uint to int64 bug fix
[MERGE #2067 @Cellule] WASM - uint to int64 bug fix

Merge pull request #2067 from Cellule:users/micfer/wasm/uint_long

Use MOV_TRUNC instead of MOV when converting an unsigned int to int64

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