Credential Manager: Add a 'formData' property to LocalCredential.

LayoutTests/http/tests/credentialmanager/localcredential-basics.html

Index: LayoutTests/http/tests/credentialmanager/localcredential-basics.html
diff --git a/LayoutTests/http/tests/credentialmanager/localcredential-basics.html b/LayoutTests/http/tests/credentialmanager/localcredential-basics.html
index 75912ec268fa67551e30587b62ddcf1b7f3769a5..23464cb8308f64237d68db3cbbb3b796371ef288 100644
--- a/LayoutTests/http/tests/credentialmanager/localcredential-basics.html
+++ b/LayoutTests/http/tests/credentialmanager/localcredential-basics.html
@@ -8,12 +8,14 @@ test(function() {
     var credential = new LocalCredential('id', 'pencil', 'name', 'https://example.com/avatar.png');
 
     verifyInterface('LocalCredential', credential, {
+        formData: 'object',
         id: 'string',
         name: 'string',
         avatarURL: 'string',
         password: 'string'
     });
 
+    assert_true(credential.formData instanceof FormData);
     assert_equals(credential.id, 'id');
     assert_equals(credential.name, 'name');
     assert_equals(credential.avatarURL, 'https://example.com/avatar.png');
@@ -44,5 +46,5 @@ test(function() {
     assert_equals(credential.avatarURL, '');
     assert_equals(credential.password, 'pencil');
 
-}, 'Construct a LocalCredential with an empty namd and avatar URL.');
+}, 'Construct a LocalCredential with an empty name and avatar URL.');
 </script>