What does this MR do?

there's no reason to trim before assigning to q.value (which gets reflected to the <input> control and ends up trimming end spaces when back-spacing)

the stated reason for messing with the control's own value every time it changes, is to handle changes while Android is composing; I've tested that, while I'm composing a character with my input method on X11, search responds to each keypress, and I think it's good enough