Google pubsub - undefined method `empty?' for nil:NilClass

[durandom]

workaround for regression reported fog/fog-google#214

[NoMethodError]: undefined method `empty?' for nil:NilClass
/opt/rh/cfme-gemset/gems/fog-google-0.5.2/lib/fog/google/requests/pubsub/create_subscription.rb:29:in `create_subscription'
/opt/rh/cfme-gemset/gems/fog-google-0.5.2/lib/fog/google/models/pubsub/subscription.rb:71:in `save'
/opt/rh/cfme-gemset/gems/fog-core-1.43.0/lib/fog/core/collection.rb:51:in `create'

My guess is either fog/fog-google#168 introduced this regression because this line passes push_config and if it's nil it will pass nil.

fixes https://bugzilla.redhat.com/show_bug.cgi?id=1442690
@miq-bot add_labels fine/yes, bug, providers/google
@miq-bot assign @agrare

[miq-bot]

Checked commit durandom@a117e8a with ruby 2.2.6, rubocop 0.47.1, and haml-lint 0.20.0
1 file checked, 0 offenses detected
Everything looks good. ⭐

[simaishi]

Fine backport details:

$ git log -1
commit b10da52879b5824e598242a35706d33baed78890
Author: Adam Grare <agrare@redhat.com>
Date:   Mon Apr 24 14:38:35 2017 -0400

    Merge pull request #14856 from durandom/google_pubsub
    
    Google pubsub - undefined method `empty?' for nil:NilClass
    (cherry picked from commit 7edd38f086833e8cc360acd2e92e169bf082089f)
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1445083