Remove unused BackgroundAnimationType to simplify translate delegate.

components/translate/core/browser/translate_infobar_delegate.h

Index: components/translate/core/browser/translate_infobar_delegate.h
diff --git a/components/translate/core/browser/translate_infobar_delegate.h b/components/translate/core/browser/translate_infobar_delegate.h
index eee41f3b00427b1dd4859be8698685601c2ee6d4..6a8a77b94dbb3de095bcfff8d57f2ea1170a0868 100644
--- a/components/translate/core/browser/translate_infobar_delegate.h
+++ b/components/translate/core/browser/translate_infobar_delegate.h
@@ -37,13 +37,6 @@ class TranslateManager;
 
 class TranslateInfoBarDelegate : public infobars::InfoBarDelegate {
  public:
-  // The types of background color animations.
-  enum BackgroundAnimationType {
-    NONE,
-    NORMAL_TO_ERROR,
-    ERROR_TO_NORMAL
-  };
-
   static const size_t kNoIndex;
 
   ~TranslateInfoBarDelegate() override;
@@ -124,12 +117,6 @@ class TranslateInfoBarDelegate : public infobars::InfoBarDelegate {
     return triggered_from_menu_;
   }
 
-  // Returns what kind of background fading effect the infobar should use when
-  // its is shown.
-  BackgroundAnimationType background_animation_type() const {
-    return background_animation_;
-  }
-
   virtual void Translate();
   virtual void RevertTranslation();
   void ReportLanguageDetectionError();
@@ -200,7 +187,6 @@ class TranslateInfoBarDelegate : public infobars::InfoBarDelegate {
       const base::WeakPtr<TranslateManager>& translate_manager,
       bool is_off_the_record,
       translate::TranslateStep step,
-      TranslateInfoBarDelegate* old_delegate,
       const std::string& original_language,
       const std::string& target_language,
       TranslateErrors::Type error_type,
@@ -220,10 +206,6 @@ class TranslateInfoBarDelegate : public infobars::InfoBarDelegate {
   bool is_off_the_record_;
   translate::TranslateStep step_;
 
-  // The type of fading animation if any that should be used when showing this
-  // infobar.
-  BackgroundAnimationType background_animation_;
-
   TranslateUIDelegate ui_delegate_;
   base::WeakPtr<TranslateManager> translate_manager_;