ToNumber should return NaN if there's embedded NULL (fixes #5038)
ToNumber should return NaN if there's embedded NULL (fixes #5038)

The bug is in JavascriptString::ToDouble. After skipping whitespace characters,
the function determines if the string is empty by checking if pch points to \0.
This bug makes the function incorrectly return 0 for string "\x00". It should
check the length, instead of null terminator.

Fixes #5038

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