Fix prop validation in constructor (fixes #259)

Author: yannickcr

lib/rules/prop-types.js

@@ -331,10 +331,11 @@ module.exports = function(context) {
    * @return {string} the name of the property or undefined if not found
    */
   function getPropertyName(node) {
-    if (componentUtil.getNode(context, node) && !inConstructor()) {
-      if (node.object.name === 'props') {
-        return void 0;
-      }
+    var directProp = /^props\./.test(context.getSource(node));
+    if (directProp && componentUtil.getNode(context, node) && !inConstructor(node)) {
+      return void 0;
+    }
+    if (!directProp) {
       node = node.parent;
     }
     var property = node.property;