The selection region is wrong when changing mode between visual line mode and visual mode

## Reproduce

- Open a new terminal.
- Enter below content.
```zsh
123456
abcdef
```
- Enter visual mode and select region from `3` to `c`.
- Stroke `Shift-V` to the visual line mode.
- Stroke `v` to change back to visual mode.

## Result

1) The selection region is only one line when changing to visual line mode.
2) The selection region is wrong when changing back to visual mode.

