p12 path not saving in credentials.xml

[craigdbarber]

.p12 file not recordings in credentials.xml and empty(has size 0 bytes (placed in folder \gauth))

Steps to reproduce:

1. install google-oauth-plugin
2. go to Jenkins Dashboard
3. login as Administrator
4. go to Credentials
5. Select "Global credentials (unrestricted)"
6. Select "Add Credentials"
7. Kind - Google Service account from private key
8. Provide any "Project Name"
9. Select option "P12 key"
10. Fill "E-Mail Address"
11. provide p12 key
12. press "ok"
13. Look into credentials.xml in Jenkins home folder

e-mail for project filled, but no path to p12 key
14) Check size of p12 key in folder "gauth"
size of p12 key is 0 bytes
On Jenkins installed in Debian 8 by deb file all works fine.

[craigdbarber]

Migrated from: https://issues.jenkins-ci.org/browse/JENKINS-31638

[stephenashank]

Made obsolete by #19 and #48. Keyfiles are no longer stored directly, the Jenkins credentials store holds the secret after uploading the keyfile.