Update from Google.

--
MOE_MIGRATED_REVID=85702957
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/Token.java b/src/main/java/com/google/devtools/build/lib/syntax/Token.java
new file mode 100644
index 0000000..e3bcfec
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/syntax/Token.java
@@ -0,0 +1,50 @@
+// Copyright 2014 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package com.google.devtools.build.lib.syntax;
+
+/**
+ * A Token represents an actual lexeme; that is, a lexical unit, its location in
+ * the input text, its lexical kind (TokenKind) and any associated value.
+ */
+public class Token {
+
+  public final TokenKind kind;
+  public final int left;
+  public final int right;
+  public final Object value;
+
+  public Token(TokenKind kind, int left, int right) {
+    this(kind, left, right, null);
+  }
+
+  public Token(TokenKind kind, int left, int right, Object value) {
+    this.kind = kind;
+    this.left = left;
+    this.right = right;
+    this.value = value;
+  }
+
+  /**
+   * Constructs an easy-to-read string representation of token, suitable for use
+   * in user error messages.
+   */
+  @Override
+  public String toString() {
+    // TODO(bazel-team): do proper escaping of string literals
+    return kind == TokenKind.STRING     ? ("\"" + value + "\"")
+        : value == null                 ? kind.getPrettyName()
+        : value.toString();
+  }
+
+}