DevTools: Add JSDoc for static methods, fix JSDoc types and induced errors

Source/devtools/front_end/timeline/TimelineView.js

Index: Source/devtools/front_end/timeline/TimelineView.js
diff --git a/Source/devtools/front_end/timeline/TimelineView.js b/Source/devtools/front_end/timeline/TimelineView.js
index 5d378591c6855e3752dbc0f6e13026f14ea64b1c..5eab0caee9de81e52021592a063c46237e20d0e4 100644
--- a/Source/devtools/front_end/timeline/TimelineView.js
+++ b/Source/devtools/front_end/timeline/TimelineView.js
@@ -652,7 +652,7 @@ WebInspector.TimelineView.prototype = {
         var taskIndex = insertionIndexForObjectInListSortedByFunction(startTime, tasks, compareEndTime);
 
         var foreignStyle = "gpu-task-foreign";
-        var element = container.firstChild;
+        var element = /** @type {?Element} */ (container.firstChild);

[aandrey, 2014/06/17 11:33:54]

should be no cast

[apavlov, 2014/06/17 12:46:04]

same as above

         var lastElement;
         var lastLeft;
         var lastRight;
@@ -1101,7 +1101,7 @@ WebInspector.TimelineRecordListRow.prototype = {
     },
 
     /**
-     * @param {!Event} event
+     * @param {?Event} event
      */
     _onExpandClick: function(event)
     {