Generate API docs during build.

utils/apidoc/scripts/list_files.dart

Index: utils/apidoc/scripts/list_files.dart
diff --git a/utils/apidoc/scripts/list_files.dart b/utils/apidoc/scripts/list_files.dart
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index 0000000000000000000000000000000000000000..e62a8254aa2c5b9e10f296d4fa3f5431a2454952
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+++ b/utils/apidoc/scripts/list_files.dart
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+// 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.
+
+/**
+ * Traverses apidoc and dartdoc and lists all possible input files that are
+ * used when building API documentation. Used by gyp to determine when apidocs
+ * need to be regenerated (see `apidoc.gyp`).
+ */
+#library('list_files');
+
+#import('dart:io');
+
+final allowedExtensions = const [
+  '.css', '.dart', '.ico', '.js', '.json', '.png', '.sh', '.txt'
+];
+
+void main() {
+  final scriptDir = new File(new Options().script).directorySync().path;
+  final dartDir = '$scriptDir/../../../';
+  listFiles('$dartDir/utils/apidoc');
+  listFiles('$dartDir/lib/dartdoc');
+}
+
+void listFiles(String dirPath) {
+  final dir = new Directory(dirPath);
+
+  dir.onFile = (path) {
+    if (allowedExtensions.indexOf(extension(path)) != -1) {
+      print(path);
+    }
+  };
+
+  dir.list(recursive: true);
+}
+
+String extension(String path) {
+  int lastDot = path.lastIndexOf('.');
+  if (lastDot == -1) return '';
+
+  return path.substring(lastDot);
+}