Update Physical Web WebUI to show new results automatically

components/physical_web/webui/resources/physical_web.js

Index: components/physical_web/webui/resources/physical_web.js
diff --git a/components/physical_web/webui/resources/physical_web.js b/components/physical_web/webui/resources/physical_web.js
index 70d856fe7db71a2222280e9cda9630a922507d4b..b050945951938506355bfc04751d0abe32defa84 100644
--- a/components/physical_web/webui/resources/physical_web.js
+++ b/components/physical_web/webui/resources/physical_web.js
@@ -9,27 +9,36 @@
  *      nearby devices
  */
 function renderTemplate(nearbyUrlsData) {
+  if (nearbyUrlsData['metadata'].length != 0) {
+    $('empty-list-container').hidden = true;
+  }
+  // This is a workaround with jstemplate. Jstemplate render only works on empty
+  // node. When we need to rerender things, we have to remove previous nodes.
+  let renderContainer = document.getElementById('render-container');
+  // Remove existing childNode.
+  while (renderContainer.hasChildNodes()) {
+    renderContainer.removeChild(renderContainer.lastChild);
+  }
+  let templateDiv = document.getElementById('render-template').cloneNode(true);
+  renderContainer.appendChild(templateDiv);
+
   // This is the javascript code that processes the template:
-  jstProcess(new JsEvalContext(nearbyUrlsData), $('physicalWebTemplate'));
+  jstProcess(new JsEvalContext(nearbyUrlsData), templateDiv);
+
+  let bodyContainer = $('body-container');
+  bodyContainer.hidden = false;
 }
 
-function requestNearbyURLs() {
-  chrome.send('requestNearbyURLs');
+function physicalWebPageLoaded() {
+  chrome.send('physicalWebPageLoaded');
 }
 
 function physicalWebItemClicked(index) {
   chrome.send('physicalWebItemClicked', [index]);
 }
 
-function returnNearbyURLs(nearbyUrlsData) {
-  var bodyContainer = $('body-container');
+function pushNearbyURLs(nearbyUrlsData) {
   renderTemplate(nearbyUrlsData);
-  bodyContainer.hidden = false;
-
-  if (nearbyUrlsData['metadata'].length == 0) {
-    var emptyMessage = $('empty-list-container');
-    emptyMessage.hidden = false;
-  }
 }
 
-document.addEventListener('DOMContentLoaded', requestNearbyURLs);
+document.addEventListener('DOMContentLoaded', physicalWebPageLoaded);