Remove some appending behavior from GN.

tools/gn/operators_unittest.cc

Index: tools/gn/operators_unittest.cc
diff --git a/tools/gn/operators_unittest.cc b/tools/gn/operators_unittest.cc
index 16d626f0b33effb1f752437dc9f2c39359ef3666..7d59640cc581ad9a4869e6530a9821e02b67b8c1 100644
--- a/tools/gn/operators_unittest.cc
+++ b/tools/gn/operators_unittest.cc
@@ -22,6 +22,15 @@ bool IsValueStringEqualing(const Value& v, const char* s) {
   return v.string_value() == s;
 }
 
+// Returns a list populated with a single literal Value corresponding to the
+// given token. The token must outlive the list (since the list will just
+// copy the reference).
+scoped_ptr<ListNode> ListWithLiteral(const Token& token) {
+  scoped_ptr<ListNode> list(new ListNode);
+  list->append_item(scoped_ptr<ParseNode>(new LiteralNode(token)));
+  return list.Pass();
+}
+
 }  // namespace
 
 TEST(Operators, SourcesAppend) {
@@ -50,21 +59,21 @@ TEST(Operators, SourcesAppend) {
   // Append an integer.
   const char integer_value[] = "5";
   Token integer(Location(), Token::INTEGER, integer_value);
-  node.set_right(scoped_ptr<ParseNode>(new LiteralNode(integer)));
+  node.set_right(ListWithLiteral(integer).PassAs<ParseNode>());
   node.Execute(setup.scope(), &err);
   EXPECT_FALSE(err.has_error());
 
   // Append a string that doesn't match the pattern, it should get appended.
   const char string_1_value[] = "\"good\"";
   Token string_1(Location(), Token::STRING, string_1_value);
-  node.set_right(scoped_ptr<ParseNode>(new LiteralNode(string_1)));
+  node.set_right(ListWithLiteral(string_1).PassAs<ParseNode>());
   node.Execute(setup.scope(), &err);
   EXPECT_FALSE(err.has_error());
 
   // Append a string that does match the pattern, it should be a no-op.
   const char string_2_value[] = "\"foo-rm\"";
   Token string_2(Location(), Token::STRING, string_2_value);
-  node.set_right(scoped_ptr<ParseNode>(new LiteralNode(string_2)));
+  node.set_right(ListWithLiteral(string_2).PassAs<ParseNode>());
   node.Execute(setup.scope(), &err);
   EXPECT_FALSE(err.has_error());