Remove dart2jslib.dart

pkg/compiler/lib/src/dart_backend/dart_backend.dart

Index: pkg/compiler/lib/src/dart_backend/dart_backend.dart
diff --git a/pkg/compiler/lib/src/dart_backend/dart_backend.dart b/pkg/compiler/lib/src/dart_backend/dart_backend.dart
index bd16595124411d295e6011211d63d52f5977ca2b..c0d0e7ffe41fe8198656297f685484a5e1566538 100644
--- a/pkg/compiler/lib/src/dart_backend/dart_backend.dart
+++ b/pkg/compiler/lib/src/dart_backend/dart_backend.dart
@@ -7,21 +7,42 @@ library dart_backend;
 import 'dart:async' show Future;
 import 'dart:math' show max;
 
-import '../../compiler.dart' show CompilerOutputProvider;
-import '../elements/elements.dart';
-import '../dart2jslib.dart';
-import '../dart_types.dart';
-import '../diagnostic_listener.dart';
+import '../../compiler.dart' show
+    CompilerOutputProvider;
+import '../common/backend_api.dart' show
+    Backend;
+import '../common/codegen.dart' show
+    CodegenWorkItem;
+import '../common/registry.dart' show
+    Registry;
+import '../common/resolution.dart' show
+    ResolutionCallbacks;
+import '../common/tasks.dart' show
+    CompilerTask;
+import '../compiler.dart' show
+    Compiler,
+    isPrivateName;
 import '../compile_time_constants.dart';
 import '../constants/constant_system.dart';
 import '../constants/expressions.dart';
 import '../constants/values.dart';
+import '../dart_types.dart';
+import '../diagnostic_listener.dart';
+import '../diagnostics/invariant.dart' show
+    invariant;
+import '../diagnostics/spannable.dart' show
+    NO_LOCATION_SPANNABLE,
+    Spannable,
+    SpannableAssertionFailure;
+import '../elements/elements.dart';
 import '../enqueue.dart' show
     Enqueuer,
     ResolutionEnqueuer,
     WorldImpact;
-import '../library_loader.dart' show LoadedLibraries;
-import '../messages.dart' show MessageKind;
+import '../library_loader.dart' show
+    LoadedLibraries;
+import '../messages.dart' show
+    MessageKind;
 import '../mirror_renamer/mirror_renamer.dart';
 import '../resolution/resolution.dart' show
     TreeElements,