Fix that holding volume buttons to activate Extra dim feature doesn't do anything.

Root cause:
Original framework design which has 3 seconds restriction to prevent users from easily triggering the accessibility volume shortcut when first time using it.

Solution:
The system would bypass the 3 seconds restriction if users manually set any feature as the volume key shortcut.

Bug: 202602908
Test: manual test
Change-Id: Iace0804fc36809f7cf39d19850c1bbd8ba9fca02