Remove Compiler and JavaScriptBackend from program_builder and collector.

pkg/compiler/lib/src/js_emitter/program_builder/registry.dart

 // Copyright (c) 2014, 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.js_emitter.program_builder;
 
 /// Maps [LibraryElement]s to their [Element]s.
 ///
 /// Fundamentally, this class nicely encapsulates a
 /// `Map<LibraryElement, List<Element>>`.
@@ skipping 33 matching lines @@
   }
 }
 
 /// Keeps track of all elements and holders.
 ///
 /// This class assigns each registered element to its [LibrariesMap] (which are
 /// in bijection with [OutputUnit]s).
 ///
 /// Registered holders are assigned a name.
 class Registry {
-  final Compiler _compiler;
+  final DeferredLoadTask _deferredLoadTask;
   final Map<String, Holder> _holdersMap = <String, Holder>{};
   final Map<OutputUnit, LibrariesMap> _deferredLibrariesMap =
       <OutputUnit, LibrariesMap>{};
 
   /// Cache for the last seen output unit.
   OutputUnit _lastOutputUnit;
   LibrariesMap _lastLibrariesMap;
 
-  DeferredLoadTask get _deferredLoadTask => _compiler.deferredLoadTask;
   Iterable<Holder> get holders => _holdersMap.values;
   Iterable<LibrariesMap> get deferredLibrariesMap =>
       _deferredLibrariesMap.values;
 
   // Add one for the main libraries map.
   int get librariesMapCount => _deferredLibrariesMap.length + 1;
 
   LibrariesMap mainLibrariesMap;
 
-  Registry(this._compiler);
+  Registry(this._deferredLoadTask);
 
   OutputUnit get _mainOutputUnit => _deferredLoadTask.mainOutputUnit;
 
   LibrariesMap _mapUnitToLibrariesMap(OutputUnit targetUnit) {
     if (targetUnit == _lastOutputUnit) return _lastLibrariesMap;
 
     LibrariesMap result = (targetUnit == _mainOutputUnit)
         ? mainLibrariesMap
         : _deferredLibrariesMap[targetUnit];
 
@@ skipping 35 matching lines @@
         (_holdersMap[name].isStaticStateHolder == isStaticStateHolder &&
             _holdersMap[name].isConstantsHolder == isConstantsHolder));
 
     return _holdersMap.putIfAbsent(name, () {
       return new Holder(name, _holdersMap.length,
           isStaticStateHolder: isStaticStateHolder,
           isConstantsHolder: isConstantsHolder);
     });
   }
 }