Enable caret event detection for IA2Web (#16815)
Fixes #11545
Summary of the issue:
We do not rely on caret events for IA2.
Description of user facing changes
Possibly slightly faster caret navigation in Firefox and Chrome.
Description of development approach
No longer ignore caret events for IA2Web objects
Ignore the location change and show events for IA2, rather, rely on IA2_EVENT_TEXT_CARET_MOVED
