Organic Groups Views Contextual Filters
Under Relationships, I choose "OG membership: OG membership from Node". 

Then under Contextual Filters, I choose "OG membership: Group ID". 

The last step is to select the Provide default value and choose "Type: Current OG group from context" under the WHEN THE FILTER VALUE IS NOT IN THE URL heading. Attached is a picture of what I mean.

Contextual Filter setup