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

tools/isolate/PRESUBMIT.py

+# 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))
+  output.extend(
+      input_api.canned_checks.RunUnitTestsInDirectory(
+          input_api, output_api,
+          input_api.PresubmitLocalPath(),
+          whitelist=[r'.+_test\.py$']))
+  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)