Remove final users of dart:profiler library

pkg/compiler/lib/src/common/tasks.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // 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.
 
 library dart2js.common.tasks;
 
-import 'dart:profiler' show
+import 'dart:developer' show
     UserTag;
 import '../compiler.dart' show
     Compiler;
 import '../diagnostics/diagnostic_listener.dart' show
     DiagnosticReporter;
 import '../elements/elements.dart' show
     Element;
 
 typedef void DeferredAction();
 
@@ skipping 71 matching lines @@
 
   int getSubtaskTime(String subtask) => _subtasks[subtask].timing;
 }
 
 class GenericTask extends CompilerTask {
   final String name;
 
   GenericTask(this.name, Compiler compiler)
       : super(compiler);
 }