Use delegated fixtures in Rackspace identity.
diff --git a/rackspace/identity/v2/extensions/delegate.go b/rackspace/identity/v2/extensions/delegate.go
index 3500cfd..fc547cd 100644
--- a/rackspace/identity/v2/extensions/delegate.go
+++ b/rackspace/identity/v2/extensions/delegate.go
@@ -3,49 +3,22 @@
 import (
 	"github.com/rackspace/gophercloud"
 	common "github.com/rackspace/gophercloud/openstack/common/extensions"
-	os "github.com/rackspace/gophercloud/openstack/identity/v2/extensions"
 	"github.com/rackspace/gophercloud/pagination"
 )
 
-// ExtensionPage is the page returned by a pager when traversing over a collection of extensions.
-type ExtensionPage struct {
-	common.ExtensionPage
-}
-
-// IsEmpty checks whether an ExtensionPage struct is empty.
-func (r ExtensionPage) IsEmpty() (bool, error) {
-	is, err := ExtractExtensions(r)
-	if err != nil {
-		return true, err
-	}
-	return len(is) == 0, nil
-}
-
 // ExtractExtensions accepts a Page struct, specifically an ExtensionPage struct, and extracts the
 // elements into a slice of os.Extension structs.
-func ExtractExtensions(page pagination.Page) ([]os.Extension, error) {
-	exts, err := common.ExtractExtensions(page.(ExtensionPage).ExtensionPage)
-	if err != nil {
-		return nil, err
-	}
-	results := make([]os.Extension, len(exts))
-	for i, ext := range exts {
-		results[i] = os.Extension{Extension: ext}
-	}
-	return results, nil
+func ExtractExtensions(page pagination.Page) ([]common.Extension, error) {
+	return common.ExtractExtensions(page)
 }
 
 // Get retrieves information for a specific extension using its alias.
-func Get(c *gophercloud.ServiceClient, alias string) os.GetResult {
-	return os.Get(c, alias)
+func Get(c *gophercloud.ServiceClient, alias string) common.GetResult {
+	return common.Get(c, alias)
 }
 
 // List returns a Pager which allows you to iterate over the full collection of extensions.
 // It does not accept query parameters.
 func List(c *gophercloud.ServiceClient) pagination.Pager {
-	return os.List(c).WithPageCreator(func(r pagination.LastHTTPResponse) pagination.Page {
-		return ExtensionPage{
-			ExtensionPage: common.ExtensionPage{SinglePageBase: pagination.SinglePageBase(r)},
-		}
-	})
+	return common.List(c)
 }