Remove language directory.

dart/language/grammar/TestGrammar.java

-// Copyright (c) 2011, 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.
-
-package com.google.dart.antlr;
-
-import org.antlr.runtime.ANTLRFileStream;
-import org.antlr.runtime.CharStream;
-import org.antlr.runtime.CommonTokenStream;
-
-/**
- * Test rig for testing the Dart grammar.
- */
-public class TestGrammar {
-  public static void main(String... arguments) throws Exception {
-    boolean hasErrors = false;
-    if (arguments.length == 0) {
-      throw new AssertionError("No files given on command line");
-    }
-    for (String argument : arguments) {
-      CharStream input = new ANTLRFileStream(argument, "UTF8");
-      DartLexer lexer = new DartLexer(input);
-      CommonTokenStream tokens = new CommonTokenStream(lexer);
-      DartParser parser = new DartParser(tokens);
-      if (argument.endsWith(".lib")) {
-        parser.libraryUnit();
-      } else if (argument.endsWith(".dart")) {
-        parser.compilationUnit();
-      } else {
-        throw new AssertionError("Unknown file type: " + argument);
-      }
-      hasErrors |= lexer.hasErrors;
-      hasErrors |= parser.hasErrors;
-    }
-    if (hasErrors) {
-      throw new AssertionError("Parse errors");
-    }
-  }
-}