Remove generated directories with 100s of files.

client/html/generated/html/frog/FileWriter.dart

Index: client/html/generated/html/frog/FileWriter.dart
diff --git a/client/html/generated/html/frog/FileWriter.dart b/client/html/generated/html/frog/FileWriter.dart
deleted file mode 100644
index dd9eadcc3d3210b2bdfcf9a702f6173a761b0da2..0000000000000000000000000000000000000000
--- a/client/html/generated/html/frog/FileWriter.dart
+++ /dev/null
@@ -1,37 +0,0 @@
-
-class _FileWriterImpl implements FileWriter native "*FileWriter" {
-
-  static final int DONE = 2;
-
-  static final int INIT = 0;
-
-  static final int WRITING = 1;
-
-  final _FileErrorImpl error;
-
-  final int length;
-
-  EventListener onabort;
-
-  EventListener onerror;
-
-  EventListener onprogress;
-
-  EventListener onwrite;
-
-  EventListener onwriteend;
-
-  EventListener onwritestart;
-
-  final int position;
-
-  final int readyState;
-
-  void abort() native;
-
-  void seek(int position) native;
-
-  void truncate(int size) native;
-
-  void write(_BlobImpl data) native;
-}