cros-suggest: add feature flag to ime service

Make the assistive multi word suggestions flag available to the IME
service.

Bug: 1146266
Change-Id: Iba1f3c15ea8386fe3374f2ed45454616c49ca15a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2580640Reviewed-by: Darren Shen <shend@chromium.org>
Commit-Queue: Curtis McMullan <curtismcmullan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#835095}

chromeos/services/ime/ime_service.cc

@@ -105,6 +105,9 @@ void ImeService::RunInMainSequence(ImeSequencedTask task, int task_id) {
 }
 
 bool ImeService::IsFeatureEnabled(const char* feature_name) {
+  if (strcmp(feature_name, "AssistiveMultiWord") == 0) {
+    return base::FeatureList::IsEnabled(chromeos::features::kAssistMultiWord);
+  }
   if (strcmp(feature_name, "SystemLatinPhysicalTyping") == 0) {
     return base::FeatureList::IsEnabled(
         chromeos::features::kSystemLatinPhysicalTyping);