DevTools: draw load/first paint marks as tall vertical delimiters

Source/devtools/front_end/timeline/TracingTimelineUIUtils.js

Index: Source/devtools/front_end/timeline/TracingTimelineUIUtils.js
diff --git a/Source/devtools/front_end/timeline/TracingTimelineUIUtils.js b/Source/devtools/front_end/timeline/TracingTimelineUIUtils.js
index 53f7af700db588ed72d7b5c59f8135410d5e85cb..32736d3b34e50a17bb7401e6ded70dbc0aad37af 100644
--- a/Source/devtools/front_end/timeline/TracingTimelineUIUtils.js
+++ b/Source/devtools/front_end/timeline/TracingTimelineUIUtils.js
@@ -341,6 +341,15 @@ WebInspector.TracingTimelineUIUtils.isMarkerEvent = function(event)
 
 /**
  * @param {!WebInspector.TracingModel.Event} event
+ * @return {boolean}
+ */
+WebInspector.TracingTimelineUIUtils.isTallMarkerEvent = function(event)
+{
+    return event.name !== WebInspector.TracingTimelineModel.RecordType.TimeStamp;
+}
+
+/**
+ * @param {!WebInspector.TracingModel.Event} event
  * @param {!WebInspector.Linkifier} linkifier
  * @return {?Node}
  */