Adjust fill dialog UI

1. Make rounded corners on the Fill dialog.
2. Fixed the position of the secondary button in the fill dialog
   and save UI.
3. Change the text of the secondary button in the fill dialog
   to "No thinks".
4. Reduce the size of the icon in the fill dialog.
5. Darken the outside of the fill dialog.

Bug: 213136422
Test: Manual
Change-Id: Ieecaa6b777ffd0600b88b29a18c1c48b1394a431