Correct. But old one (in CharsetConverter) is outdated, allow utf-8 5 and 6 bytes sequences and was based on never confirmed RFC.
This one is based on latest standard version (Unicode 6.3.0, even if URL looks like 6.2.0), placed on correct file/class and return 3 codes.
If this PR will be merged, I'll remove old function and replace usage of it with new one.