Show augmented autofill suggestion inline iff both augmented autofill service...

Show augmented autofill suggestion inline iff both augmented autofill service and ime support inline.

* Also did a bit of refactoring to move IME create inline suggestion request callback handling to a separate class for better thread safety.

Test: manual
Bug: 147463211

Change-Id: Iee544ff7da588d5f951aca0b7f5144334c2d88a2