add experimental param to control the triggering threshold to default Always Translate checked

components/translate/core/browser/translate_ui_delegate.cc

Index: components/translate/core/browser/translate_ui_delegate.cc
diff --git a/components/translate/core/browser/translate_ui_delegate.cc b/components/translate/core/browser/translate_ui_delegate.cc
index 50879397171f0a66a0c9c50180aea59e27d7a43e..d9e2b511b6625875ab7e64d7a292d4fb3c1a60e0 100644
--- a/components/translate/core/browser/translate_ui_delegate.cc
+++ b/components/translate/core/browser/translate_ui_delegate.cc
@@ -302,14 +302,15 @@ bool TranslateUIDelegate::ShouldAlwaysTranslate() {
 }
 
 bool TranslateUIDelegate::ShouldAlwaysTranslateBeCheckedByDefault() {
-  // After 2 clicks on Translate for the same language.
-  // We check for == 2 instead of >= 2 because if the user translates with the
+  // After N clicks on Translate for the same language.
+  // We check for == N instead of >= N because if the user translates with the
   // "Always do this?" on, then the next time the bubble won't show up.
   // The only chance the bubble will show up is after the user manually unchecks
   // "Always do this?". In that case, since it is after user explictly unchecks,
-  // we should show as it as unchecked so we only check == 2 instead of >= 2.
+  // we should show as it as unchecked so we only check == N instead of >= N.
   return ShouldAlwaysTranslate() ||
-         prefs_->GetTranslationAcceptedCount(GetOriginalLanguageCode()) == 2;
+         prefs_->ShouldAlwaysTranslateBeCheckedByDefault(
+             GetOriginalLanguageCode());
 }
 
 void TranslateUIDelegate::SetAlwaysTranslate(bool value) {