Add Function based profile tree

runtime/observatory/lib/utils.dart

Index: runtime/observatory/lib/utils.dart
diff --git a/runtime/observatory/lib/src/app/utils.dart b/runtime/observatory/lib/utils.dart
similarity index 95%
rename from runtime/observatory/lib/src/app/utils.dart
rename to runtime/observatory/lib/utils.dart
index eff1a17ca447388ce71eb0a79cf1e036bba20e49..58d18aaf1563870b7f7396d7f1b88df18f6e9aaa 100644
--- a/runtime/observatory/lib/src/app/utils.dart
+++ b/runtime/observatory/lib/utils.dart
@@ -2,12 +2,14 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-part of app;
+library utils;
+
+import 'dart:math';
 
 class Utils {
   static String formatPercent(num a, num total) {
-      var percent = 100.0 * (a / total);
-      return '${percent.toStringAsFixed(2)}%';
+    var percent = 100.0 * (a / total);
+    return '${percent.toStringAsFixed(2)}%';
   }
 
   static String zeroPad(int value, int pad) {
@@ -110,7 +112,6 @@ class Utils {
 
     var seconds = millis ~/ millisPerSecond;
 
-    StringBuffer out = new StringBuffer();
     if (hours != 0) {
       return '${hours}h ${minutes}m ${seconds}s';
     }