Bug 966159 - Fix TypeError when trying to unlink account. r=ckarlof

services/fxaccounts/FxAccounts.jsm

@@ -143,9 +143,14 @@ InternalMethods.prototype = {
         return data;
       }
       if (!this.whenKeysReadyPromise) {
-        this.whenKeysReadyPromise = this.fetchAndUnwrapKeys(data.keyFetchToken);
+        this.whenKeysReadyPromise = Promise.defer();
+        this.fetchAndUnwrapKeys(data.keyFetchToken).then(data => {
+          if (this.whenKeysReadyPromise) {
+            this.whenKeysReadyPromise.resolve(data);
+          }
+        });
       }
-      return this.whenKeysReadyPromise;
+      return this.whenKeysReadyPromise.promise;
     });
    },