[Android] Log uncaught Java exceptions when running native tests.

Currently, Java exceptions hit while running native tests -- e.g. on JNI link
failure -- are lost to the logcat. This surfaces them to the test runner's
stdout.

BUG=

Review-Url: https://codereview.chromium.org/1982493002
Cr-Original-Commit-Position: refs/heads/master@{#393921}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 6cdb933c8d2c4cadbf842fbb3ceb9cecd0f70920

android/pylib/local/device/local_device_gtest_run.py

@@ -4,6 +4,7 @@
 
 import collections
 import itertools
+import logging
 import os
 import posixpath
 
@@ -311,9 +312,13 @@ class LocalDeviceGtestRun(local_device_test_run.LocalDeviceTestRun):
     @local_device_test_run.handle_shard_failures_with(
         on_failure=self._env.BlacklistDevice)
     def list_tests(dev):
-      tests = self._delegate.Run(
+      raw_test_list = self._delegate.Run(
           None, dev, flags='--gtest_list_tests', timeout=30)
-      tests = gtest_test_instance.ParseGTestListTests(tests)
+      tests = gtest_test_instance.ParseGTestListTests(raw_test_list)
+      if not tests:
+        logging.info('No tests found. Output:')
+        for l in raw_test_list:
+          logging.info('  %s', l)
       tests = self._test_instance.FilterTests(tests)
       return tests