[Android] Stop tearing down the test runner's SIGTERM handler.

build/android/test_runner.py

Index: build/android/test_runner.py
diff --git a/build/android/test_runner.py b/build/android/test_runner.py
index 505bd2a10a1b1ab7a58418127eea76f75f27c8f3..a42f757d23ff841d20a9b056400b22ad219e2fb9 100755
--- a/build/android/test_runner.py
+++ b/build/android/test_runner.py
@@ -27,7 +27,6 @@ from devil.android import forwarder
 from devil.android import ports
 from devil.utils import reraiser_thread
 from devil.utils import run_tests_helper
-from devil.utils import signal_handler
 
 from pylib import constants
 from pylib.base import base_test_result
@@ -718,8 +717,7 @@ def RunTestsInPlatformMode(args):
 
     infra_error('\n'.join(msg))
 
-  sigterm_handler = signal_handler.SignalHandler(
-      signal.SIGTERM, unexpected_sigterm)
+  signal.signal(signal.SIGTERM, unexpected_sigterm)
 
   ### Set up results handling.
   # TODO(jbudorick): Rewrite results handling.
@@ -761,7 +759,7 @@ def RunTestsInPlatformMode(args):
 
   ### Run.
 
-  with sigterm_handler, json_writer, env, test_instance, test_run:
+  with json_writer, env, test_instance, test_run:
 
     repetitions = (xrange(args.repeat + 1) if args.repeat >= 0
                    else itertools.count())