[iOS] Japanese keyboard shown by Qt doesn't work similarly as the native iOS keyboard

1) Add "Japanese - Kana" keyboard type on System preference.
2) Run attached sample
3) Tap on TextEdit area to show Japanese keyboard.
4) Press key "あ".
5) As a result, text shift pre-edit status. (Texts in green rectangle area are candidate for converting)

Expected:
The right bottom key should "確定" instead of "改行"

Actual:
The right bottom key is "改行"

• "確定" means fix
• "改行" means linefeed.
• The right bottom key should show "確定" while pre-edit status.

This issue only happens on beginning of a line.
You can confirm by continuing following steps

6) Press key "改行"
7) Touch after "あ"
8) Press "あ" again.
9) The right bottom key shown "確定" as expected. (See jp-key-issue06.png)"