Do not recalculate string length in error_string
Do not recalculate string length in error_string

According to https://msdn.microsoft.com/en-us/library/windows/desktop/ms679351(v=vs.85).aspx:

> If the function succeeds, the return value is the number of TCHARs stored in the output buffer,
> excluding the terminating null character.

aidancully/rust,GBGamer/rust,graydon/rust,aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,graydon/rust,GBGamer/rust,aidancully/rust,GBGamer/rust,GBGamer/rust,graydon/rust,aidancully/rust,GBGamer/rust,graydon/rust