DevTools: [timeline tree view] (unattributed) costs include extension overhead in Domain grouping

BUG=522614

Review URL: https://codereview.chromium.org/1305373002

git-svn-id: svn://svn.chromium.org/blink/trunk@201034 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/devtools/front_end/timeline/TimelineTreeView.js

@@ -188,11 +188,14 @@ WebInspector.TimelineTreeView.prototype = {
          */
         function groupByDomain(groupSubdomains, node)
         {
-            var parsedURL = (WebInspector.TimelineTreeView.eventURL(node.event) || "").asParsedURL();
+            var url = WebInspector.TimelineTreeView.eventURL(node.event) || "";
+            if (url.startsWith("extensions::"))
+                return groupSubdomains ? WebInspector.UIString("Chrome Extensions Overhead") : url;
+            var parsedURL = url.asParsedURL();
             if (!parsedURL)
                 return "";
             if (parsedURL.scheme === "chrome-extension") {
-                var url = parsedURL.scheme + "://" + parsedURL.host;
+                url = parsedURL.scheme + "://" + parsedURL.host;
                 var displayName = executionContextNamesByOrigin.get(url);
                 return displayName ? WebInspector.UIString("Chrome Extension: %s", displayName) : url;
             }