Change call-sites in trace viewer to use generators instead of iteration functions.

perf_insights/perf_insights/mappers/trace_stats.html

Index: perf_insights/perf_insights/mappers/trace_stats.html
diff --git a/perf_insights/perf_insights/mappers/trace_stats.html b/perf_insights/perf_insights/mappers/trace_stats.html
index 7da64b6178f229feaff3fa06279c3859c149fc53..9eb638f8b5d07ad6e8e6b76616d9172cbe9cecde 100644
--- a/perf_insights/perf_insights/mappers/trace_stats.html
+++ b/perf_insights/perf_insights/mappers/trace_stats.html
@@ -26,7 +26,7 @@ tr.exportTo('pi.m', function() {
     var categories = {};
 
     var seconds_counts = {};
-    model.iterateAllEvents(function(event) {
+    for (var event of model.descendantEvents()) {
       eventCount += 1;
       if (event.start < firstTime)
         firstTime = event.start;
@@ -45,7 +45,7 @@ tr.exportTo('pi.m', function() {
         seconds_counts[second] = 0;
 
       seconds_counts[second]++;
-    });
+    }
 
     var histogram = COUNT_NUMERIC_BUILDER.build();