[Fix] displayName (but really, propTypes detection): do not crash on empty flow type spreads

Fixes #2570.

Author: ljharb

lib/util/ast.js

@@ -168,6 +168,9 @@ function getKeyValue(context, node) {
   if (node.type === 'GenericTypeAnnotation') {
     return node.id.name;
   }
+  if (node.type === 'ObjectTypeAnnotation') {
+    return;
+  }
   const key = node.key || node.argument;
   return key.type === 'Identifier' ? key.name : key.value;
 }

tests/lib/rules/display-name.js

@@ -482,6 +482,13 @@ ruleTester.run('display-name', rule, {
         return <div>{items}</div>;
       }
     `
+  }, {
+    code: `
+      import {Component} from "react";
+      type LinkProps = {...{}};
+      class Link extends Component<LinkProps> {}
+    `,
+    parser: parsers.BABEL_ESLINT
   }],
 
   invalid: [{