add defensive coding to support experimental object spread properties

Author: Morantron

lib/rules/display-name.js

@@ -158,6 +158,10 @@ module.exports = function(context) {
     ObjectExpression: function(node) {
       // Search for the displayName declaration
       node.properties.forEach(function(property) {
+        if (!property.key) {
+          return;
+        }
+
         if (!isDisplayNameDeclaration(property.key)) {
           return;
         }

lib/rules/jsx-sort-prop-types.js

@@ -81,6 +81,10 @@ module.exports = function(context) {
 
     ObjectExpression: function(node) {
       node.properties.forEach(function(property) {
+        if (!property.key) {
+          return;
+        }
+
         if (!isPropTypesDeclaration(property.key)) {
           return;
         }