Move common URIs to common/names.dart

pkg/compiler/lib/src/dart_backend/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.
 
 part of dart_backend;
 
 // TODO(ahe): This class is simply wrong.  This backend should use
 // elements when it can, not AST nodes.  Perhaps a [Map<Element,
 // TreeElements>] is what is needed.
 class ElementAst {
@@ skipping 212 matching lines @@
       if (library.isPlatformLibrary) {
         library.forEachLocalMember((Element element) {
           if (element.isClass) {
             ClassElement classElement = element;
             classElement.ensureResolved(compiler);
           }
         });
       }
     });
     if (useMirrorHelperLibrary &&
-        loadedLibraries.containsLibrary(Compiler.DART_MIRRORS)) {
+        loadedLibraries.containsLibrary(Uris.dart_mirrors)) {
       return compiler.libraryLoader.loadLibrary(
           compiler.translateResolvedUri(
-              loadedLibraries.getLibrary(Compiler.DART_MIRRORS),
+              loadedLibraries.getLibrary(Uris.dart_mirrors),
               MirrorRenamerImpl.DART_MIRROR_HELPER, null)).
           then((LibraryElement library) {
         mirrorRenamer = new MirrorRenamerImpl(compiler, this, library);
       });
     }
     return new Future.value();
   }
 
   @override
   void registerStaticUse(Element element, Enqueuer enqueuer) {
@@ skipping 269 matching lines @@
   }
 
   // TODO(johnniwinther): Remove this when values are computed from the
   // expressions.
   @override
   void copyConstantValues(DartConstantTask task) {
     constantCompiler.constantValueMap.addAll(
         task.constantCompiler.constantValueMap);
   }
 }