Remove generated directories with 100s of files.

client/html/generated/html/dartium/FileWriterSync.dart

Index: client/html/generated/html/dartium/FileWriterSync.dart
diff --git a/client/html/generated/html/dartium/FileWriterSync.dart b/client/html/generated/html/dartium/FileWriterSync.dart
deleted file mode 100644
index 0504dc13d03fde81775ec384448cb5e4007d4a7f..0000000000000000000000000000000000000000
--- a/client/html/generated/html/dartium/FileWriterSync.dart
+++ /dev/null
@@ -1,23 +0,0 @@
-
-class _FileWriterSyncImpl extends _DOMTypeBase implements FileWriterSync {
-  _FileWriterSyncImpl._wrap(ptr) : super._wrap(ptr);
-
-  int get length() => _wrap(_ptr.length);
-
-  int get position() => _wrap(_ptr.position);
-
-  void seek(int position) {
-    _ptr.seek(_unwrap(position));
-    return;
-  }
-
-  void truncate(int size) {
-    _ptr.truncate(_unwrap(size));
-    return;
-  }
-
-  void write(Blob data) {
-    _ptr.write(_unwrap(data));
-    return;
-  }
-}