Fix this usage in jsx-no-undef (fixes #489)

Author: yannickcr

lib/rules/jsx-no-undef.js

@@ -32,6 +32,11 @@ module.exports = function(context) {
     var i;
     var len;
 
+    // Ignore 'this' keyword (also maked as JSXIdentifier when used in JSX)
+    if (node.name === 'this') {
+      return;
+    }
+
     while (scope.type !== 'global') {
       scope = scope.upper;
       variables = scope.variables.concat(variables);

tests/lib/rules/jsx-no-undef.js

@@ -45,6 +45,17 @@ ruleTester.run('jsx-no-undef', rule, {
   }, {
     code: '/*eslint no-undef:1*/ var React, app; React.render(<app.foo.Bar />);',
     parserOptions: parserOptions
+  }, {
+    code: [
+      '/*eslint no-undef:1*/',
+      'var React;',
+      'class Hello extends React.Component {',
+      '  render() {',
+      '    return <this.props.tag />',
+      '  }',
+      '}'
+    ].join('\n'),
+    parserOptions: parserOptions
   }],
   invalid: [{
     code: '/*eslint no-undef:1*/ var React; React.render(<App />);',