Revert revision 33053

third_party/pkg/angular/lib/perf/dev_tools_timeline.dart

 part of angular.perf;
 
 class DevToolsTimelineProfiler extends Profiler {
   final dom.Console console = dom.window.console;
   String prefix = '';
 
-  String startTimer(String name, [String extraData]) {
+  int startTimer(String name, [String extraData]) {
     console.time('$prefix$name');
     prefix = '$prefix  ';
-    return name;
   }
 
   void stopTimer(dynamic name) {
     prefix = prefix.length > 0 ? prefix.substring(0, prefix.length - 2) : prefix;
     console.timeEnd('$prefix$name');
   }
 
   void markTime(String name, [String extraData]) {
     console.timeStamp('$prefix$name');
   }
 }