Testable patch parser.

dart/tests/compiler/dart2js/mock_compiler.dart

Index: dart/tests/compiler/dart2js/mock_compiler.dart
diff --git a/dart/tests/compiler/dart2js/mock_compiler.dart b/dart/tests/compiler/dart2js/mock_compiler.dart
index bb71b40f9e2dfc19d526b4642cf0d9a6a569a37d..4642f23d4ba2790a8a73a37b5c605393b6746035 100644
--- a/dart/tests/compiler/dart2js/mock_compiler.dart
+++ b/dart/tests/compiler/dart2js/mock_compiler.dart
@@ -171,14 +171,18 @@ class MockCompiler extends Compiler {
    * is fixed to export its top-level declarations.
    */
   LibraryElement createLibrary(String name, String source) {
-    Uri uri = new Uri.fromComponents(scheme: "source", path: name);
-    var script = new Script(uri, new MockFile(source));
-    var library = new LibraryElementX(script);
+    var library = createUnparsedLibrary(name, source);
     parseScript(source, library);
     library.setExports(library.localScope.values.toList());
     return library;
   }
 
+  LibraryElement createUnparsedLibrary(String name, String source) {
+    Uri uri = new Uri.fromComponents(scheme: "source", path: name);
+    var script = new Script(uri, new MockFile(source));
+    return new LibraryElementX(script);
+  }
+
   void reportWarning(Node node, var message) {
     warnings.add(new WarningMessage(node, message.message));
   }