Remove generated directories with 100s of files.

client/html/generated/html/dartium/DataTransferItem.dart

Index: client/html/generated/html/dartium/DataTransferItem.dart
diff --git a/client/html/generated/html/dartium/DataTransferItem.dart b/client/html/generated/html/dartium/DataTransferItem.dart
deleted file mode 100644
index 6f0ae3bff4fb7ccc1d533cfc99b993dd3302c89c..0000000000000000000000000000000000000000
--- a/client/html/generated/html/dartium/DataTransferItem.dart
+++ /dev/null
@@ -1,22 +0,0 @@
-
-class _DataTransferItemImpl extends _DOMTypeBase implements DataTransferItem {
-  _DataTransferItemImpl._wrap(ptr) : super._wrap(ptr);
-
-  String get kind() => _wrap(_ptr.kind);
-
-  String get type() => _wrap(_ptr.type);
-
-  Blob getAsFile() {
-    return _wrap(_ptr.getAsFile());
-  }
-
-  void getAsString([StringCallback callback = null]) {
-    if (callback === null) {
-      _ptr.getAsString();
-      return;
-    } else {
-      _ptr.getAsString(_unwrap(callback));
-      return;
-    }
-  }
-}