Move common URIs to common/names.dart

pkg/compiler/lib/src/js_backend/js_backend.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.
 
 library js_backend;
 
 import 'dart:async' show EventSink, Future;
 import 'dart:collection' show HashMap;
 
 import 'package:js_runtime/shared/embedded_names.dart' as embeddedNames;
 import 'package:js_runtime/shared/embedded_names.dart' show JsGetName;
 
 import '../closure.dart';
 import '../common/backend_api.dart' show
     Backend;
 import '../common/codegen.dart' show
     CodegenRegistry,
     CodegenWorkItem;
 import '../common/names.dart' show
     Identifiers,
-    Selectors;
+    Selectors,
+    Uris;
 import '../common/registry.dart' show
     Registry;
 import '../common/tasks.dart' show
     CompilerTask;
 import '../common/resolution.dart' show
     ResolutionCallbacks;
 import '../common/work.dart' show
     ItemCompilationContext;
 import '../compiler.dart' show
     Compiler,
@@ skipping 63 matching lines @@
 part 'constant_handler_javascript.dart';
 part 'custom_elements_analysis.dart';
 part 'frequency_namer.dart';
 part 'field_naming_mixin.dart';
 part 'minify_namer.dart';
 part 'namer.dart';
 part 'namer_names.dart';
 part 'no_such_method_registry.dart';
 part 'runtime_types.dart';
 part 'type_variable_handler.dart';