now returns false on bad role_data

lib/ansible/galaxy/role.py

@@ -182,6 +182,7 @@ class GalaxyRole(object):
         """
         Downloads the archived role from github to a temp location
         """
+        if role_data:
 
             # first grab the file and save it to a temp location
             if "github_user" in role_data and "github_repo" in role_data:
@@ -203,6 +204,7 @@ class GalaxyRole(object):
                 # TODO: better urllib2 error handling for error
                 #       messages that are more exact
                 self.display.error("failed to download the file.")
+
         return False
 
     def install(self, role_filename):