[omnibox][spark] Ranking tweak - 0 min matches for scoped inputs

Before, at least 1 strong or 2 weak matches were required, or the
suggestion was filtered out.

Now, this requirement only applies to unscoped inputs.

This allows inputs like '@spark d' to show suggestions.

Bug: 392732729, 399900518
Change-Id: I1b3059f817cb2f040031c3eaec8486d0086ab429
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6336259
Reviewed-by: Justin Donnelly <jdonnelly@chromium.org>
Commit-Queue: Justin Donnelly <jdonnelly@chromium.org>
Auto-Submit: manuk hovanesian <manukh@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1430295}