Make CompilerTask independent of compiler.

pkg/compiler/lib/src/ssa/optimize.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.
 
 import '../common/codegen.dart' show CodegenWorkItem;
 import '../common/tasks.dart' show CompilerTask;
 import '../compiler.dart' show Compiler;
 import '../constants/constant_system.dart';
 import '../constants/values.dart';
 import '../core_types.dart' show CoreClasses;
@@ skipping 18 matching lines @@
 
 abstract class OptimizationPhase {
   String get name;
   void visitGraph(HGraph graph);
 }
 
 class SsaOptimizerTask extends CompilerTask {
   final JavaScriptBackend backend;
   SsaOptimizerTask(JavaScriptBackend backend)
       : this.backend = backend,
-        super(backend.compiler);
+        super(backend.compiler.measurer);
   String get name => 'SSA optimizer';
   Compiler get compiler => backend.compiler;
   Map<HInstruction, Range> ranges = <HInstruction, Range>{};
 
   void optimize(CodegenWorkItem work, HGraph graph) {
     void runPhase(OptimizationPhase phase) {
       measureSubtask(phase.name, () => phase.visitGraph(graph));
       compiler.tracer.traceGraph(phase.name, graph);
       assert(graph.isValid());
     }
@@ skipping 2331 matching lines @@
 
     keyedValues.forEach((receiver, values) {
       result.keyedValues[receiver] =
           new Map<HInstruction, HInstruction>.from(values);
     });
 
     result.nonEscapingReceivers.addAll(nonEscapingReceivers);
     return result;
   }
 }