Add android.test.. jars to update script

The android.test.. jars are needed for supporting tests in unbundled
branches without pulling framework/base and its dependencies.

Bug: 30188076
Test: run script and check generated commit

Change-Id: I5f498bded8bfc29dad1799534bb58fd5aab25319
diff --git a/update_current.py b/update_current.py
index ba3e081..a5e14c9 100755
--- a/update_current.py
+++ b/update_current.py
@@ -261,6 +261,8 @@
         extract_to(zipFile, paths, 'android.jar', current_path)
         extract_to(zipFile, paths, 'uiautomator.jar', current_path)
         extract_to(zipFile, paths, 'framework.aidl', current_path)
+        extract_to(zipFile, paths, 'optional/android.test.mock.jar', current_path)
+        extract_to(zipFile, paths, 'optional/android.test.runner.jar', current_path)
 
         # Unclear if this is actually necessary.
         extract_to(zipFile, paths, 'framework.aidl', system_path)