First half of the new HTML json docs.

tools/dom/docs/bin/docs.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.
+
+/**
+ * This program reads the HTML libraries from [LIB_PATH] and outputs their
+ * documentation to [JSON_PATH].
+ */
+
+import 'dart:io';
+import 'dart:async';
+
+import '../lib/docs.dart';
+
+final Path json_path = scriptDir.append('../docs.json').canonicalize();
+final Path lib_path = scriptDir.append('../../../../sdk/').canonicalize();
+
+main() {
+  print('Converting HTML docs from $lib_path to $json_path.');
+
+  var anyErrors = convert(lib_path, json_path);
+
+  print('Converted HTML docs ${anyErrors ? "with $anyErrors" : "without"}'
+    ' errors.');
+}
+
+/**
+ * Gets the full path to the directory containing the entrypoint of the current
+ * script.
+ */
+Path get scriptDir =>
+    new Path(new Options().script).directoryPath;