Suggestions: Only pass explicitly handled keys to Suggestions list.

This change ensures that the Omnibox Suggestions list will not attempt
to interpret keystrokes that should be handled by the Omnibox. One
such example is the SPACE key, which can occasionally be consumed by
views to simulate click/long press.

Bug: 344930378
Change-Id: I53e3e7c98b2d5b01222911f95ce4a01fab22bfb3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6533820
Reviewed-by: Calder Kitagawa <ckitagawa@chromium.org>
Commit-Queue: Tomasz Wiszkowski <ender@google.com>
Cr-Commit-Position: refs/heads/main@{#1459118}