Add --test-jar arg to test_runner to explicitly specify its path.

build/android/gyp/create_test_runner_script.py

Index: build/android/gyp/create_test_runner_script.py
diff --git a/build/android/gyp/create_test_runner_script.py b/build/android/gyp/create_test_runner_script.py
index 2b46e862af1c2225e7d89f40cc140e2a497cd4e5..511882f69b22f48c2fb535d659f305d5edb1de91 100755
--- a/build/android/gyp/create_test_runner_script.py
+++ b/build/android/gyp/create_test_runner_script.py
@@ -64,6 +64,7 @@ def main(args):
   group.add_argument('--output-directory')
   group.add_argument('--runtime-deps-path')
   group.add_argument('--test-apk')
+  group.add_argument('--test-jar')
   group.add_argument('--test-apk-incremental-install-script')
   group.add_argument('--coverage-dir')
   args, test_runner_args = parser.parse_known_args(
@@ -109,6 +110,9 @@ def main(args):
   if args.test_apk:
     test_runner_path_args.append(
         ('--test-apk', RelativizePathToScript(args.test_apk)))
+  if args.test_jar:
+    test_runner_path_args.append(
+        ('--test-jar', RelativizePathToScript(args.test_jar)))
   if args.test_apk_incremental_install_script:
     test_runner_path_args.append(
         ('--test-apk-incremental-install-script',