Change layerTreeAsText to default to layer lists.

third_party/WebKit/LayoutTests/compositing/squashing/dont-squash-with-scale-transform.html

Index: third_party/WebKit/LayoutTests/compositing/squashing/dont-squash-with-scale-transform.html
diff --git a/third_party/WebKit/LayoutTests/compositing/squashing/dont-squash-with-scale-transform.html b/third_party/WebKit/LayoutTests/compositing/squashing/dont-squash-with-scale-transform.html
index 77ac31a86286266089466a4adb992b4935cff7af..943daa39db635a9eac71ac82f4eaa513b160f032 100644
--- a/third_party/WebKit/LayoutTests/compositing/squashing/dont-squash-with-scale-transform.html
+++ b/third_party/WebKit/LayoutTests/compositing/squashing/dont-squash-with-scale-transform.html
@@ -16,14 +16,14 @@ if (window.testRunner)
     testRunner.dumpAsText();
 onload = function() {
     if (window.internals) {
-        var layers = JSON.parse(internals.layerTreeAsText(document, internals.LAYER_TREE_INCLUDES_DEBUG_INFO));
+        var layers = JSON.parse(internals.layerTreeAsText(document, internals.LAYER_TREE_INCLUDES_DEBUG_INFO))["layers"];
 
         // The scale-transform layer can't be squashed
-        assert_true(layers.children[0].children[1].children[0].compositingReasons[1] == "Layer was separately composited because it could not be squashed.");
-        assert_true(layers.children[0].children[1].children[0].squashingDisallowedReasons[0] == "Cannot squash layers with transforms that are not identity or translation.");
+        assert_true(layers[3].compositingReasons[1] == "Layer was separately composited because it could not be squashed.");
+        assert_true(layers[3].squashingDisallowedReasons[0] == "Cannot squash layers with transforms that are not identity or translation.");
 
         // ...but the translate-transform one can.
-        assert_true(layers.children[0].children[1].children[1].compositingReasons[0] == "Secondary layer, home for a group of squashable content");
+        assert_true(layers[4].compositingReasons[0] == "Secondary layer, home for a group of squashable content");
     }
 };
 </script>