Draft: inputmethod: Explicitly send empty pre-edit string when cleared
When a pre-edit is cleared, TextInputV1 and V2 explicitly send a null empty pre-edit.
TextInputV3 does not, this is fine according to the docs:
Values set with this event are double-buffered. They must be applied and reset to initial on the next zwp_text_input_v3.done event. The initial value of text is an empty string, and cursor_begin, cursor_end and cursor_hidden are all 0.
Gnome does, so some clients (Chromium) rely on it.
Draft as I don't think it's needed. It's just ready depending on what the original bug reporter says.