VIM-705 Fix repeated multiline indent

Fixes https://youtrack.jetbrains.com/issue/VIM-705

When a visual mode command is repeated, code calls into
MotionGroup#toggleVisual() to setup a 'fake' visual mode selection. But
when MotionGroup.moveCaret() is called, it notices that the indent
command has the FLAG_EXIT_VISUAL flag, and leaves visual mode right
away.

Though all tests pass, I'm a bit unsure whether this could break other things.