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

third_party/WebKit/Source/core/xml/XPathGrammar.y

Index: third_party/WebKit/Source/core/xml/XPathGrammar.y
diff --git a/third_party/WebKit/Source/core/xml/XPathGrammar.y b/third_party/WebKit/Source/core/xml/XPathGrammar.y
index 83836325e68cb485ab376ca4e295f72b74c725a7..28d326b48ac429c571d9a185009677e0af1c0427 100644
--- a/third_party/WebKit/Source/core/xml/XPathGrammar.y
+++ b/third_party/WebKit/Source/core/xml/XPathGrammar.y
@@ -275,12 +275,12 @@ PredicateList:
     Predicate
     {
         $$ = new blink::HeapVector<blink::Member<Predicate>>;
-        $$->append(new Predicate($1));
+        $$->push_back(new Predicate($1));
     }
     |
     PredicateList Predicate
     {
-        $$->append(new Predicate($2));
+        $$->push_back(new Predicate($2));
     }
     ;
 
@@ -359,12 +359,12 @@ ArgumentList:
     Argument
     {
         $$ = new blink::HeapVector<blink::Member<Expression>>;
-        $$->append($1);
+        $$->push_back($1);
     }
     |
     ArgumentList ',' Argument
     {
-        $$->append($3);
+        $$->push_back($3);
     }
     ;