Fix emoji suggestion browsing with up arrow

It wasn't working properly because I forgot to add handling of
SuggestionStatus::kBrowsing enum.

Bug: 1068855
Change-Id: I0e96f0ab4ab587a80d26d022c1a1e415ea1b6c0a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2141479Reviewed-by: Keith Lee <keithlee@chromium.org>
Commit-Queue: My Nguyen <myy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#758675}

chrome/browser/chromeos/input_method/assistive_suggester.cc

@@ -77,6 +77,8 @@ bool AssistiveSuggester::OnKeyEvent(
       case SuggestionStatus::kDismiss:
         current_suggester_ = nullptr;
         return false;
+      case SuggestionStatus::kBrowsing:
+        return true;
       default:
         break;
     }