Override checkInputConnectionProxy in SearchView.

SearchView's editor is SearchView#SearchAutoComplete. In order to
correctly determine if SearchView's inner editor has the current
InputConnection, SearchView#SearchAutoComplete must override
check InputConnectionProxy to return true.
Note: this change will also be cherrypicked to jetpack

Bug: 112399521
Test: Manually tested using steps mentioned in bug.
Change-Id: If4d202d0070974cbda4cb3c78febe3049001972b