Revert "Remove dart2js specific core.dart and coreimpl.dart files."

lib/compiler/implementation/lib/coreimpl.dart

Index: lib/compiler/implementation/lib/coreimpl.dart
diff --git a/lib/compiler/implementation/lib/coreimpl.dart b/lib/compiler/implementation/lib/coreimpl.dart
new file mode 100644
index 0000000000000000000000000000000000000000..241574ae3af507a783f9c032173f60cf5f5499d3
--- /dev/null
+++ b/lib/compiler/implementation/lib/coreimpl.dart
@@ -0,0 +1,31 @@
+// 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.
+
+#library('dart:coreimpl');
+
+#import('dart:math');
+#import('js_helper.dart');
+
+#source('../../../../lib/coreimpl/arrays.dart');
+#source('../../../../lib/coreimpl/collections.dart');
+#source('../../../../lib/coreimpl/date.dart');
+#source('../../../../lib/coreimpl/dual_pivot_quicksort.dart');
+#source('../../../../lib/coreimpl/duration_implementation.dart');
+#source('../../../../lib/coreimpl/exceptions.dart');
+#source('../../../../lib/coreimpl/expando.dart');
+#source('../../../../lib/coreimpl/future_implementation.dart');
+#source('../../../../lib/coreimpl/hash_map_set.dart');
+#source('../../../../lib/coreimpl/linked_hash_map.dart');
+#source('../../../../lib/coreimpl/list.dart');
+#source('../../../../lib/coreimpl/maps.dart');
+#source('../../../../lib/coreimpl/options.dart');
+#source('../../../../lib/coreimpl/print.dart');
+#source('../../../../lib/coreimpl/queue.dart');
+#source('../../../../lib/coreimpl/regexp.dart');
+#source('../../../../lib/coreimpl/splay_tree.dart');
+#source('../../../../lib/coreimpl/stopwatch_implementation.dart');
+#source('../../../../lib/coreimpl/string.dart');
+#source('../../../../lib/coreimpl/string_buffer.dart');
+
+#source('mockimpl.dart');