Introduce a button to toggle hiding/showing of the details in the events tab.

chrome/browser/resources/sync_internals/events.js

Index: chrome/browser/resources/sync_internals/events.js
diff --git a/chrome/browser/resources/sync_internals/events.js b/chrome/browser/resources/sync_internals/events.js
index 0cda0860a6c521b6e6e31fc79c06bab09677f89f..3cb01c8dc594acaa7551ae743fa4d46d298cff60 100644
--- a/chrome/browser/resources/sync_internals/events.js
+++ b/chrome/browser/resources/sync_internals/events.js
@@ -3,7 +3,16 @@
 // found in the LICENSE file.
 
 (function() {
-function makeLogEntryNode(entry) {

[kjiwa, 2013/11/04 23:48:45]

You can also add 'use strict' to enable strict mode:
http://ejohn.org/blog/ecmascript-5-strict-mode-json-and-more/.

+var toggleDisplayDetails = function() {
+  var detailsNode = this.parentNode.getElementsByClassName('details')[0];
+  if (detailsNode.style.display == 'block') {
+    detailsNode.style.display = 'none';
+  } else {
+    detailsNode.style.display = 'block';
+  }
+}
+
+var makeLogEntryNode = function(entry) {
   var timeNode = document.createElement('td');
   timeNode.textContent = entry.date;
 
@@ -15,7 +24,13 @@ function makeLogEntryNode(entry) {
 
   var details = document.createElement('pre');
   details.textContent = JSON.stringify(entry.details, null, 2);
+  details.style.display = 'none';
+  details.className = 'details';
+  var detailsToggleButton = document.createElement('button');
+  detailsToggleButton.addEventListener('click', toggleDisplayDetails, false);
+  detailsToggleButton.textContent = 'Show/Hide Details';
   var detailsNode = document.createElement('td');
+  detailsNode.appendChild(detailsToggleButton);
   detailsNode.appendChild(details);
 
   var node = document.createElement('tr');