Remove the Vector::append overload that takes a Vector

Source/core/editing/TextCheckingHelper.cpp

Index: Source/core/editing/TextCheckingHelper.cpp
diff --git a/Source/core/editing/TextCheckingHelper.cpp b/Source/core/editing/TextCheckingHelper.cpp
index 091585afd09bc948b0ada8dad3bf6839db2e433b..8add3a4db8eec3c2e1d139f129db5c5f3ba09781 100644
--- a/Source/core/editing/TextCheckingHelper.cpp
+++ b/Source/core/editing/TextCheckingHelper.cpp
@@ -559,7 +559,7 @@ void checkTextOfParagraph(TextCheckerClient& client, const String& text, TextChe
         if (results.isEmpty())
             results.swap(spellingResult);
         else
-            results.append(spellingResult);
+            results.appendVector(spellingResult);
     }
 }