Navigation bar: IME cursor, (1/2):

Thanks to SlimRoms:
https://github.com/SlimRoms/frameworks_base/commit/f347c82915875f6a8c35d4152ba3ce422457af75
https://github.com/SlimRoms/frameworks_base/commit/9cb419644ecb5fd09bacc6711200fc33b2afc1b5

included:
- Enable/disable IME cursor
- Left arrow click: cursor left
- Left arrow longclick: cursor one line up
- Left arrow longclick hold: faster several lines up
- Right arrow click: cursor right
- Right arrow longclick: cursor one line down
- Right arrow longclick hold: faster several lines down