typing: add stub functions for `cext/charencoding`
I'm not sure if it's better to have a separate file, and currently pytype
doesn't really know how to handle these, so it's no help in figuring that out.
Technically, these methods are part of the `mercurial.cext.parsers` module, so
put them into the existing stub until there's a reason to split it out.
BasedOnStyle: LLVM
IndentWidth: 8
UseTab: ForIndentation
BreakBeforeBraces: Linux
AllowShortIfStatementsOnASingleLine: false
IndentCaseLabels: false
AllowShortBlocksOnASingleLine: false
AllowShortFunctionsOnASingleLine: false
IncludeCategories:
- Regex: '^<'
Priority: 1
- Regex: '^"'
Priority: 2