Revert "[lensoverlay] Language picker should hide when hover off."

This is being reverted as it was deemed as the UX was deemed awkward.
An alternative approach is being considered at crbug.com/377956763.

This is not a clean revert as we are keeping some of the general lint
fixes. But all functionality has been removed.

This reverts commit 96813cc0fd47cd411fcdddadeed27eea2a198b5b.

Change-Id: I379ba56b104961a3991b0c1a64722df50af02748
Bug: b:372939826
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6003593
Reviewed-by: Duncan Mercer <mercerd@google.com>
Auto-Submit: Juan Mojica <juanmojica@google.com>
Commit-Queue: Juan Mojica <juanmojica@google.com>
Cr-Commit-Position: refs/heads/main@{#1379999}