avoid generate_username when user is already invalid
avoid generate_username when user is already invalid

pickettd/code-dot-org,rvarshney/code-dot-org,pickettd/code-dot-org,pickettd/code-dot-org,dillia23/code-dot-org,rvarshney/code-dot-org,pickettd/code-dot-org,pickettd/code-dot-org,pickettd/code-dot-org,dillia23/code-dot-org,dillia23/code-dot-org,pickettd/code-dot-org,dillia23/code-dot-org,dillia23/code-dot-org,rvarshney/code-dot-org,rvarshney/code-dot-org,dillia23/code-dot-org,dillia23/code-dot-org,pickettd/code-dot-org,rvarshney/code-dot-org,rvarshney/code-dot-org,rvarshney/code-dot-org,dillia23/code-dot-org,rvarshney/code-dot-org