Migrate WTF::Vector::append() to ::push_back() in WTF::HexNumber

third_party/WebKit/Source/wtf/text/WTFString.cpp

Index: third_party/WebKit/Source/wtf/text/WTFString.cpp
diff --git a/third_party/WebKit/Source/wtf/text/WTFString.cpp b/third_party/WebKit/Source/wtf/text/WTFString.cpp
index 0cfe47326d65f40620f44f709acac7a528ad8d3e..bc751f5ab80128e614046bef1ae36b199875752b 100644
--- a/third_party/WebKit/Source/wtf/text/WTFString.cpp
+++ b/third_party/WebKit/Source/wtf/text/WTFString.cpp
@@ -58,7 +58,7 @@ Vector<char> asciiDebug(StringImpl* impl) {
     } else {
       buffer.push_back('\\');
       buffer.push_back('u');
-      appendUnsignedAsHexFixedSize(ch, buffer, 4);
+      HexNumber::appendUnsignedAsHexFixedSize(ch, buffer, 4);
     }
   }
   buffer.push_back('\0');