Improve the performance of StElem_I for some cases; fixes a perf regression exposed with NewScObject profiling.
Improve the performance of StElem_I for some cases; fixes a perf
regression exposed with NewScObject profiling.

Edit:
Slightly tighten the constraints on when to bailout on invalidated array length. (ty @rajatd)

Edit:
Fix assembly comment. (ty @rajatd)

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