When deleting crash dirs in cros VM tests, print out the file name.

R=jbudorick@chromium.org

Change-Id: Ic593c71edc288deb6aa9480b2bf9542722b38f0f
Reviewed-on: https://chromium-review.googlesource.com/1217914Reviewed-by: John Budorick <jbudorick@chromium.org>
Commit-Queue: Ben Pastene <bpastene@chromium.org>
Cr-Commit-Position: refs/heads/master@{#590485}

build/chromeos/run_vm_test.py

@@ -209,8 +209,10 @@ class GTestTest(RemoteTest):
     vm_test_script_contents += [
         # We run tests as chronos, but need to be root to rm the files. So pass
         # in the public plaintext root password to sudo via stdin.
-        'echo "test0000" | sudo -S find /var/spool/crash/ -type f -delete',
-        'echo "test0000" | sudo -S find /var/log/chrome/ -type f -delete',
+        'echo "test0000" | '
+        'sudo -S find /var/spool/crash/ -type f -print -delete',
+        'echo "test0000" | '
+        'sudo -S find /var/log/chrome/ -type f -print -delete',
         # Make sure the exit code is that of the test, and not the post-test
         # cleanup.
         'exit $test_retcode',