[folks] Factor out AFD parameter equality (for use in derived classes)

[Travis Reitter <treitter src gnome org>]

commit 67bd5f4e8b8a1b59354b08b8945ed5201b8a3eb4
Author: Travis Reitter <travis reitter collabora co uk>
Date:   Wed Oct 19 15:48:28 2011 -0700

    Factor out AFD parameter equality (for use in derived classes)
    
    Helps: bgo#662433 - AbstractFieldDetails.equal() is ambiguous about
    checking parameters.

 folks/abstract-field-details.vala |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/folks/abstract-field-details.vala b/folks/abstract-field-details.vala
index de45748..ec74bfb 100644
--- a/folks/abstract-field-details.vala
+++ b/folks/abstract-field-details.vala
@@ -236,6 +236,11 @@ public abstract class Folks.AbstractFieldDetails<T> : Object
           return false;
         }
 
+      return this.parameters_equal<T> (that);
+    }
+
+  public virtual bool parameters_equal (AbstractFieldDetails<T> that)
+    {
       /* Check that the parameter names and their values match exactly in both
        * AbstractFieldDetails objects. */
       if (this.parameters.size != that.parameters.size)