Tests that Input.imeSetComposition works and waits for JavaScript event handlers to finish.
Dispatching event
Initial value:"すしおに"

event: keydown
value: すしおに
selectionStart: 4
selectionEnd: 4
keyCode: 37
key: ArrowLeft

event: keyup
value: すしおに
selectionStart: 3
selectionEnd: 3
keyCode: 37
key: ArrowLeft

event: keydown
value: すしおに
selectionStart: 3
selectionEnd: 3
keyCode: 37
key: ArrowLeft

event: keyup
value: すしおに
selectionStart: 2
selectionEnd: 2
keyCode: 37
key: ArrowLeft

event: keydown
value: すしおに
selectionStart: 2
selectionEnd: 2
keyCode: 37
key: ArrowLeft

event: keyup
value: すしおに
selectionStart: 1
selectionEnd: 1
keyCode: 37
key: ArrowLeft

event: compositionstart
value: すしおに
selectionStart: 0
selectionEnd: 1

event: compositionupdate
value: すしおに
selectionStart: 0
selectionEnd: 1

event: beforeinput
value: すしおに
selectionStart: 0
selectionEnd: 1

event: input
value: オニしおに
selectionStart: 2
selectionEnd: 2

event: compositionupdate
value: オニしおに
selectionStart: 0
selectionEnd: 2

event: beforeinput
value: オニしおに
selectionStart: 0
selectionEnd: 2

event: input
value: オニしおに
selectionStart: 2
selectionEnd: 2

event: compositionend
value: オニしおに
selectionStart: 2
selectionEnd: 2