[android] Stop using isolate.py for data dependency management.

build/secondary/tools/swarming_client/BUILD.gn

Index: build/secondary/tools/swarming_client/BUILD.gn
diff --git a/build/secondary/tools/swarming_client/BUILD.gn b/build/secondary/tools/swarming_client/BUILD.gn
deleted file mode 100644
index f4860523c7c31d9379aa6c9e44ec73d0b2c99c1c..0000000000000000000000000000000000000000
--- a/build/secondary/tools/swarming_client/BUILD.gn
+++ /dev/null
@@ -1,14 +0,0 @@
-# Copyright 2016 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-group("isolate_py") {
-  _py_files =
-      read_file("//build/secondary/tools/swarming_client/isolate.pydeps",
-                "list lines")
-
-  # Filter out comments.
-  set_sources_assignment_filter([ "#*" ])
-  sources = _py_files
-  data = sources
-}