Implement a list tracer phase, that tries to find element types in individual lists.

sdk/lib/_internal/compiler/implementation/compiler.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.
 
 part of dart2js;
 
 /**
  * If true, print a warning for each method that was resolved, but not
  * compiled.
  */
@@ skipping 387 matching lines @@
   ResolverTask resolver;
   closureMapping.ClosureTask closureToClassMapper;
   TypeCheckerTask checker;
   ti.TypesTask typesTask;
   Backend backend;
   ConstantHandler constantHandler;
   ConstantHandler metadataHandler;
   EnqueueTask enqueuer;
   CompilerTask fileReadingTask;
   DeferredLoadTask deferredLoadTask;
+  ContainerTracer containerTracer;
   String buildId;
 
   static const SourceString MAIN = const SourceString('main');
   static const SourceString CALL_OPERATOR_NAME = const SourceString('call');
   static const SourceString NO_SUCH_METHOD = const SourceString('noSuchMethod');
   static const int NO_SUCH_METHOD_ARG_COUNT = 1;
   static const SourceString CREATE_INVOCATION_MIRROR =
       const SourceString('createInvocationMirror');
   static const SourceString INVOKE_ON = const SourceString('_invokeOn');
   static const SourceString RUNTIME_TYPE = const SourceString('runtimeType');
@@ skipping 81 matching lines @@
       fileReadingTask = new ReadingFilesTask(this),
       libraryLoader = new LibraryLoaderTask(this),
       scanner = new ScannerTask(this),
       dietParser = new DietParserTask(this),
       parser = new ParserTask(this),
       patchParser = new PatchParserTask(this),
       resolver = new ResolverTask(this),
       closureToClassMapper = new closureMapping.ClosureTask(this, closureNamer),
       checker = new TypeCheckerTask(this),
       typesTask = new ti.TypesTask(this),
+      containerTracer = new ContainerTracer(this),
       constantHandler = new ConstantHandler(this, backend.constantSystem),
       deferredLoadTask = new DeferredLoadTask(this),
       enqueuer = new EnqueueTask(this)];
 
     tasks.addAll(backend.tasks);
     metadataHandler = new ConstantHandler(
         this, backend.constantSystem, isMetadata: true);
   }
 
   Universe get resolverWorld => enqueuer.resolution.universe;
@@ skipping 868 matching lines @@
 
   void close() {}
 
   toString() => name;
 
   /// Convenience method for getting an [api.CompilerOutputProvider].
   static NullSink outputProvider(String name, String extension) {
     return new NullSink('$name.$extension');
   }
 }