(script_translator): add config translator/enable_word_completion

If unspecified, falls back to `translator/enable_completion`.

Fixed #905

src/rime/gear/script_translator.cc

@@ -176,6 +176,10 @@ ScriptTranslator::ScriptTranslator(const Ticket& ticket)
     config->GetBool(name_space_ + "/always_show_comments",
                     &always_show_comments_);
     config->GetBool(name_space_ + "/enable_correction", &enable_correction_);
+    if (!config->GetBool(name_space_ + "/enable_word_completion",
+                         &enable_word_completion_)) {
+      enable_word_completion_ = enable_completion_;
+    }
     config->GetInt(name_space_ + "/max_homophones", &max_homophones_);
     poet_.reset(new Poet(language(), config));
   }
@@ -361,8 +365,8 @@ static bool has_exact_match_phrase(Ptr ptr, Iter iter, size_t consumed) {
 bool ScriptTranslation::Evaluate(Dictionary* dict, UserDictionary* user_dict) {
   size_t consumed = syllabifier_->BuildSyllableGraph(*dict->prism());
   const auto& syllable_graph = syllabifier_->syllable_graph();
-  bool predict_word =
-      translator_->enable_completion() && start_ + consumed == end_of_input_;
+  bool predict_word = translator_->enable_word_completion() &&
+                      start_ + consumed == end_of_input_;
 
   phrase_ = dict->Lookup(syllable_graph, 0, predict_word);
   if (user_dict) {

src/rime/gear/script_translator.h

@@ -41,12 +41,14 @@ class ScriptTranslator : public Translator,
   int max_homophones() const { return max_homophones_; }
   int spelling_hints() const { return spelling_hints_; }
   bool always_show_comments() const { return always_show_comments_; }
+  bool enable_word_completion() const { return enable_word_completion_; }
 
  protected:
   int max_homophones_ = 1;
   int spelling_hints_ = 0;
   bool always_show_comments_ = false;
   bool enable_correction_ = false;
+  bool enable_word_completion_ = false;
   the<Corrector> corrector_;
   the<Poet> poet_;
 };