Use Polymer.dom with insertBefore.

tracing/tracing/ui/extras/chrome/cc/picture_debugger.html

Index: tracing/tracing/ui/extras/chrome/cc/picture_debugger.html
diff --git a/tracing/tracing/ui/extras/chrome/cc/picture_debugger.html b/tracing/tracing/ui/extras/chrome/cc/picture_debugger.html
index 0ab2fd68e6a7c4145ea974cafb4d4094a5d39849..386a505107edc63e31e1677f3d342a118d9334eb 100644
--- a/tracing/tracing/ui/extras/chrome/cc/picture_debugger.html
+++ b/tracing/tracing/ui/extras/chrome/cc/picture_debugger.html
@@ -9,8 +9,8 @@ found in the LICENSE file.
 <link rel="import" href="/tracing/extras/chrome/cc/picture.html">
 <link rel="import" href="/tracing/ui/analysis/generic_object_view.html">
 <link rel="import" href="/tracing/ui/base/drag_handle.html">
-<link rel="import" href="/tracing/ui/base/info_bar.html">
 <link rel="import" href="/tracing/ui/base/hotkey_controller.html">
+<link rel="import" href="/tracing/ui/base/info_bar.html">
 <link rel="import" href="/tracing/ui/base/list_view.html">
 <link rel="import" href="/tracing/ui/base/mouse_mode_selector.html">
 <link rel="import" href="/tracing/ui/base/overlay.html">
@@ -185,7 +185,7 @@ tr.exportTo('tr.ui.e.chrome.cc', function() {
       this.infoBar_ = document.createElement('tr-ui-b-info-bar');
       this.rasterArea_.appendChild(this.infoBar_);
 
-      this.insertBefore(middleDragHandle, rightPanel);
+      Polymer.dom(this).insertBefore(middleDragHandle, rightPanel);
 
       this.picture_ = undefined;