DevTools: Switch to using fast stack iterator to collect stacks during timeline recording.

third_party/WebKit/Source/devtools/front_end/sdk/CPUProfileDataModel.js

Index: third_party/WebKit/Source/devtools/front_end/sdk/CPUProfileDataModel.js
diff --git a/third_party/WebKit/Source/devtools/front_end/sdk/CPUProfileDataModel.js b/third_party/WebKit/Source/devtools/front_end/sdk/CPUProfileDataModel.js
index 0a7872fdc5c15b98863135737d5ba1b67cfa9fe5..f3f378553171457f3693fbb8de7e2f9f7b0a45db 100644
--- a/third_party/WebKit/Source/devtools/front_end/sdk/CPUProfileDataModel.js
+++ b/third_party/WebKit/Source/devtools/front_end/sdk/CPUProfileDataModel.js
@@ -16,6 +16,7 @@ WebInspector.CPUProfileDataModel = function(profile)
     this.profileEndTime = profile.endTime * 1000;
     this._assignParentsInProfile();
     if (this.samples) {
+        this._sortSamples();
         this._normalizeTimestamps();
         this._buildIdToNodeMap();
         this._fixMissingSamples();
@@ -156,6 +157,32 @@ WebInspector.CPUProfileDataModel.prototype = {
         }
     },
 
+    _sortSamples: function()
+    {
+        var timestamps = this.timestamps;
+        var samples = this.samples;
+        var indices = timestamps.map((x, index) => index);
+        indices.sort((a, b) => timestamps[a] - timestamps[b]);
+        for (var i = 0; i < timestamps.length; ++i) {
+            var index = indices[i];
+            if (index === i)
+                continue;
+            // Move items in a cycle.
+            var savedTimestamp = timestamps[i];
+            var savedSample = samples[i];
+            var currentIndex = i;
+            while (index !== i) {
+                samples[currentIndex] = samples[index];
+                timestamps[currentIndex] = timestamps[index];
+                currentIndex = index;
+                index = indices[index];
+                indices[currentIndex] = currentIndex;
+            }
+            samples[currentIndex] = savedSample;
+            timestamps[currentIndex] = savedTimestamp;
+        }
+    },
+
     _normalizeTimestamps: function()
     {
         var timestamps = this.timestamps;