Extract DiagnosticReporter implementation from Compiler.

pkg/compiler/lib/src/js_backend/codegen/glue.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.
 
 library code_generator_dependencies;
 
 import '../js_backend.dart';
 import '../../common/registry.dart' show
     Registry;
 import '../../compiler.dart' show
     Compiler;
 import '../../constants/values.dart';
 import '../../dart_types.dart' show
     DartType,
     TypeVariableType,
     InterfaceType;
+import '../../diagnostics/diagnostic_listener.dart' show
+    DiagnosticReporter;
+import '../../diagnostics/spannable.dart' show
+    CURRENT_ELEMENT_SPANNABLE;
 import '../../enqueue.dart' show
     CodegenEnqueuer;
 import '../../elements/elements.dart';
 import '../../js_emitter/js_emitter.dart';
 import '../../js/js.dart' as js;
 import '../../universe/selector.dart' show
     Selector;
 import '../../world.dart' show
     ClassWorld;
 
@@ skipping 12 matching lines @@
   JavaScriptBackend get _backend => _compiler.backend;
 
   CodeEmitterTask get _emitter => _backend.emitter;
 
   Namer get _namer => _backend.namer;
 
   Glue(this._compiler);
 
   ClassWorld get classWorld => _compiler.world;
 
+  DiagnosticReporter get reporter => _compiler.reporter;
+
   js.Expression constantReference(ConstantValue value) {
     return _emitter.constantReference(value);
   }
 
   reportInternalError(String message) {
-    _compiler.internalError(_compiler.currentElement, message);
+    reporter.internalError(CURRENT_ELEMENT_SPANNABLE, message);
   }
 
   bool isUsedAsMixin(ClassElement classElement) {
     return classWorld.isUsedAsMixin(classElement);
   }
 
   ConstantValue getConstantValueForVariable(VariableElement variable) {
     return _backend.constants.getConstantValueForVariable(variable);
   }
 
@@ skipping 197 matching lines @@
   ClassElement get jsMutableArrayClass => _backend.jsMutableArrayClass;
 
   bool isStringClass(ClassElement classElement) =>
       classElement == _backend.jsStringClass ||
       classElement == _compiler.stringClass;
 
   bool isBoolClass(ClassElement classElement) =>
       classElement == _backend.jsBoolClass ||
       classElement == _compiler.boolClass;
 }