[polymer] Switches .appendChild() to Polymer.dom()...appendChild()

tracing/tracing/base/base.html

Index: tracing/tracing/base/base.html
diff --git a/tracing/tracing/base/base.html b/tracing/tracing/base/base.html
index 9c9254b6c7f3ac8e79ce9745cef4437dc32602b5..53239739c8c6c0b0ade3d9f9dfc8608b9ef63f66 100644
--- a/tracing/tracing/base/base.html
+++ b/tracing/tracing/base/base.html
@@ -96,14 +96,14 @@ this.tr = (function() {
     panicElement = document.createElement('div');
     panicElement.style.webkitFlex = '1 1 auto';
     panicElement.style.overflow = 'auto';
-    panicOverlay.appendChild(panicElement);
+    Polymer.dom(panicOverlay).appendChild(panicElement);
 
     if (!document.body) {
       setTimeout(function() {
-        document.body.appendChild(panicOverlay);
+        Polymer.dom(document.body).appendChild(panicOverlay);
       }, 150);
     } else {
-      document.body.appendChild(panicOverlay);
+      Polymer.dom(document.body).appendChild(panicOverlay);
     }
   }
 
@@ -124,7 +124,7 @@ this.tr = (function() {
         '<pre id="details"></pre>';
     panicMessageEl.querySelector('#message').textContent = panicTitle;
     panicMessageEl.querySelector('#details').textContent = panicDetails;
-    panicElement.appendChild(panicMessageEl);
+    Polymer.dom(panicElement).appendChild(panicMessageEl);
 
     rawPanicMessages.push({
       title: panicTitle,