Fixed Has method as per Doug's request.

xpcom/ds/nsIProperties.idl

@@ -55,10 +55,9 @@ interface nsIProperties : nsISupports
     void set(in string prop, in nsISupports value);
 
     /**
-     * Returns true if the property with the given name exists with
-     * the given value.
+     * Returns true if the property with the given name exists.
      */
-    boolean has(in string prop, in nsIIDRef uuid, in nsISupports value);
+    boolean has(in string prop);
 };
 
 %{C++

xpcom/ds/nsPersistentProperties.cpp

@@ -341,8 +341,7 @@ nsPersistentProperties::Set(const char* prop, nsISupports* value)
 }
 
 NS_IMETHODIMP 
-nsPersistentProperties::Has(const char* prop, const nsIID & uuid, 
-                            nsISupports* expectedValue, PRBool *result)
+nsPersistentProperties::Has(const char* prop, PRBool *result)
 {
   return NS_ERROR_NOT_IMPLEMENTED;
 }

xpcom/ds/nsProperties.cpp

@@ -136,18 +136,14 @@ nsProperties::Set(const char* prop, nsISupports* value)
 }
 
 NS_IMETHODIMP
-nsProperties::Has(const char* prop, const nsIID & uuid, 
-                  nsISupports* expectedValue, PRBool *result)
+nsProperties::Has(const char* prop, PRBool *result)
 {
-    nsCOMPtr<nsISupports> value;
-    nsresult rv = Get(prop, uuid, getter_AddRefs(value));
-    if (NS_SUCCEEDED(rv)) {
-        if (value.get() == expectedValue) {
-            *result = PR_TRUE;
-            return NS_OK;
-        }
-    }
-    *result = PR_FALSE;
+    nsStringKey key(prop);
+    nsISupports* value = (nsISupports*)nsHashtable::Get(&key);
+    // XXX this is bogus because it doesn't distinguish between properties
+    // defined with a value NULL, and undefined properties, but we'll fix
+    // it later if it becomes a problem
+    *result = value != nsnull;
     return NS_OK;
 }