Add target base_unittests_run and tools/isolate/isolate.py.

tools/isolate/PRESUBMIT.py

Index: tools/isolate/PRESUBMIT.py
diff --git a/tools/isolate/PRESUBMIT.py b/tools/isolate/PRESUBMIT.py
new file mode 100644
index 0000000000000000000000000000000000000000..ed668d1df7001a44cf6543fdf7af6b8db8dd7261
--- /dev/null
+++ b/tools/isolate/PRESUBMIT.py
@@ -0,0 +1,23 @@
+# Copyright (c) 2012 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.
+
+"""Top-level presubmit script for isolate.
+
+See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts for
+details on the presubmit API built into gcl.
+"""
+
+
+def CommonChecks(input_api, output_api):
+  output = []
+  output.extend(input_api.canned_checks.RunPylint(input_api, output_api))
+  return output
+
+
+def CheckChangeOnUpload(input_api, output_api):
+  return CommonChecks(input_api, output_api)
+
+
+def CheckChangeOnCommit(input_api, output_api):
+  return CommonChecks(input_api, output_api)