diff --git a/Tools/ChangeLog b/Tools/ChangeLog
index 342bc62052ef57762a9332f194b83379ea813ef9..47d931e34fa9f6e26ce942c0d98beb0016e280cc 100644
--- a/Tools/ChangeLog
+++ b/Tools/ChangeLog
@@ -1,3 +1,15 @@
+2011-11-19  Alice Boxhall  <aboxhall@chromium.org>
+
+        Modify dashboard_base.js to optionally accept version 4 results json.
+
+        Reviewed by Ojan Vafai.
+
+        * TestResultServer/static-dashboards/dashboard_base.js:
+        (ADD_RESULTS):
+        (flattenTrie):
+        * TestResultServer/static-dashboards/flakiness_dashboard_tests.js:
+        (testFlattenTrie):
+
 2011-11-19  Ojan Vafai  <ojan@chromium.org>
 
         Stop storing results files as jsonp in the test results server
diff --git a/Tools/TestResultServer/static-dashboards/dashboard_base.js b/Tools/TestResultServer/static-dashboards/dashboard_base.js
index 52043441e26746a59a5727104b54e2dcaf10707b..0fa9c4991f9861c0f9c0dc6c7ba6472900fd2926 100644
--- a/Tools/TestResultServer/static-dashboards/dashboard_base.js
+++ b/Tools/TestResultServer/static-dashboards/dashboard_base.js
@@ -469,6 +469,7 @@ var g_resultsByBuilder = {};
 var g_expectations;
 function ADD_RESULTS(builds)
 {
+    var json_version = builds['version'];
     for (var builderName in builds) {
         if (builderName == 'version')
             continue;
@@ -481,12 +482,34 @@ function ADD_RESULTS(builds)
         if ((Date.now() / 1000) - lastRunSeconds > TWO_WEEKS_SECONDS)
             continue;
 
+        if (json_version >= 4)
+            builds[builderName][TESTS_KEY] = flattenTrie(builds[builderName][TESTS_KEY]);
         g_resultsByBuilder[builderName] = builds[builderName];
     }
 
     handleResourceLoad();
 }
 
+// TODO(aboxhall): figure out whether this is a performance bottleneck and
+// change calling code to understand the trie structure instead if necessary.
+function flattenTrie(trie, prefix)
+{
+    var result = {};
+    for (var name in trie) {
+        var fullName = prefix ? prefix + "/" + name : name;
+        var data = trie[name];
+        if ("results" in data)
+            result[fullName] = data;
+        else {
+            var partialResult = flattenTrie(data, fullName);
+            for (var key in partialResult) {
+                result[key] = partialResult[key];
+            }
+        }
+    }
+    return result;
+}
+
 function pathToBuilderResultsFile(builderName)
 {
     return TEST_RESULTS_SERVER + 'testfile?builder=' + builderName +
diff --git a/Tools/TestResultServer/static-dashboards/flakiness_dashboard_tests.js b/Tools/TestResultServer/static-dashboards/flakiness_dashboard_tests.js
index a82c1700da922cc30f377af252f35dd135f5b54d..0bcc2b782fba74e832e35f01c5fb14b9b07b41e5 100644
--- a/Tools/TestResultServer/static-dashboards/flakiness_dashboard_tests.js
+++ b/Tools/TestResultServer/static-dashboards/flakiness_dashboard_tests.js
@@ -95,7 +95,22 @@ function assertEquals(actual, expected, message)
     }
 }
 
-function throwError(resultsForTests, actual, expected) {}
+function testFlattenTrie()
+{
+    var tests = {
+        'bar.html': {'results': [[100, 'F']], 'times': [[100, 0]]},
+        'foo': {
+            'bar': {
+                'baz.html': {'results': [[100, 'F']], 'times': [[100, 0]]},
+            }
+        }
+    };
+    var expectedFlattenedTests = {
+        'bar.html': {'results': [[100, 'F']], 'times': [[100, 0]]},
+        'foo/bar/baz.html': {'results': [[100, 'F']], 'times': [[100, 0]]},
+    };
+    assertEquals(JSON.stringify(flattenTrie(tests)), JSON.stringify(expectedFlattenedTests))
+}
 
 function testReleaseFail()
 {