Expose APIs for text track settings

Source/core/testing/InternalSettings.h

Index: Source/core/testing/InternalSettings.h
diff --git a/Source/core/testing/InternalSettings.h b/Source/core/testing/InternalSettings.h
index b9b37afaa0610b928c831656827e91a364d01320..f19a438c1b16204b37643bcefa7a37bf2eb770fe 100644
--- a/Source/core/testing/InternalSettings.h
+++ b/Source/core/testing/InternalSettings.h
@@ -133,6 +133,15 @@ public:
     void setPrimaryHoverType(const String&, ExceptionState&);
     void setDnsPrefetchLogging(bool, ExceptionState&);
 
+    void setTextTrackTextColor(const String&, ExceptionState&);
+    void setTextTrackBackgroundColor(const String&, ExceptionState&);
+    void setTextTrackWindowColor(const String&, ExceptionState&);
+    void setTextTrackTextShadow(const String&, ExceptionState&);
+    void setTextTrackTextSize(const String&, ExceptionState&);
+    void setTextTrackFontFamily(const String&, ExceptionState&);
+    void setTextTrackFontStyle(const String&, ExceptionState&);
+    void setTextTrackFontVariant(const String&, ExceptionState&);
+
 private:
     explicit InternalSettings(Page&);