Support warning decorations in Timeline flame chart based on trace events

Source/devtools/front_end/timeline/TracingModel.js

Index: Source/devtools/front_end/timeline/TracingModel.js
diff --git a/Source/devtools/front_end/sdk/TracingModel.js b/Source/devtools/front_end/timeline/TracingModel.js
similarity index 90%
rename from Source/devtools/front_end/sdk/TracingModel.js
rename to Source/devtools/front_end/timeline/TracingModel.js
index 16c48114103a4da315c1eeb9229d0070b01d62cd..43d5ac9311417e6121dc07db219bedea7665bd14 100644
--- a/Source/devtools/front_end/sdk/TracingModel.js
+++ b/Source/devtools/front_end/timeline/TracingModel.js
@@ -174,6 +174,7 @@ WebInspector.TracingModel.prototype = {
 
     _tracingComplete: function()
     {
+        this._bindings = new WebInspector.TracingModel.EventBindings(this);
         this._active = false;
         if (!this._pendingStopCallback)
             return;
@@ -181,6 +182,14 @@ WebInspector.TracingModel.prototype = {
         this._pendingStopCallback = null;
     },
 
+    /**
+     * @return {!WebInspector.TracingModel.EventBindings}
+     */
+    bindings: function()
+    {
+        return this._bindings;
+    },
+
     reset: function()
     {
         this._processById = {};
@@ -192,6 +201,7 @@ WebInspector.TracingModel.prototype = {
         this._inspectedTargetMainThreadEvents = [];
         this._inspectedTargetLayerTreeHostId = 0;
         this._frameLifecycleEvents = [];
+        this._eventToWarning = new Map();

[caseq, 2014/05/08 09:03:53]

remove?

[yurys, 2014/05/08 09:47:31]

Done.

     },
 
     /**
@@ -291,6 +301,42 @@ WebInspector.TracingModel.prototype = {
 }
 
 /**
+ * @param {!WebInspector.TracingModel} model
+ * @constructor
+ */
+WebInspector.TracingModel.EventBindings = function(model) {
+    this._eventToWarning = new Map();
+    this._model = model;
+    this._calculateWarnings();
+}
+
+WebInspector.TracingModel.EventBindings.prototype = {
+    /**
+     * @param {!WebInspector.TracingModel.Event} event
+     * @return {string|undefined}
+     */
+    eventWarning: function(event)
+    {
+        return this._eventToWarning.get(event);
+    },
+
+    _calculateWarnings: function()
+    {
+        var events = this._model.inspectedTargetMainThreadEvents();
+        var currentScriptEvent = null;
+        for (var i = 0, l = events.length; i < l; i++) {

[caseq, 2014/05/08 09:03:53]

Lowercase l looks bad as identifier, let's use just "length"?

[yurys, 2014/05/08 09:47:31]

Done.

+            var event = events[i];
+            if (currentScriptEvent && event.startTime > currentScriptEvent.endTime)

[caseq, 2014/05/08 09:03:53]

Are script events never nested?

[yurys, 2014/05/08 09:47:31]

They are but we just need to know if there is at least one on the stack so it is
enough to keep only the the outermost one.

+                currentScriptEvent = null;
+            if (event.name === WebInspector.TimelineModel.RecordType.Layout && currentScriptEvent)
+                this._eventToWarning.put(event, WebInspector.UIString("Forced synchronous layout is a possible performance bottleneck."));
+            if (event.name === WebInspector.TimelineModel.RecordType.EvaluateScript || event.name === WebInspector.TimelineModel.RecordType.FunctionCall)
+                currentScriptEvent = event;
+        }
+    }
+}
+
+/**
  * @constructor
  * @param {!WebInspector.TracingModel.EventPayload} payload
  * @param {number} level