Fix an issue where "SuggestionSpan"s are not removed properly

Basically, the root cause of this issue is a lack of an expected implementation.
This change completes the spec of the architecture to remove modified "SuggestionSpan"s.

Bug: 9190860
Change-Id: I63f2ccf3407ae7c1bc28813e044b8703e2112f34
3 files changed