Add constructor to handle this

src/browser/components/LoginModal.jsx

@@ -3,6 +3,11 @@ const ReactDOM = require('react-dom');
 const {Button, Col, ControlLabel, Form, FormGroup, FormControl, Modal} = require('react-bootstrap');
 
 class LoginModal extends React.Component {
+  constructor(props) {
+    super(props);
+    this.handleSubmit = this.handleSubmit.bind(this);
+  }
+
   handleSubmit(event) {
     event.preventDefault();
     const usernameNode = ReactDOM.findDOMNode(this.refs.username);

src/browser/components/TeamListItem.jsx

@@ -1,6 +1,12 @@
 const React = require('react');
 
 class TeamListItem extends React.Component {
+  constructor(props) {
+    super(props);
+    this.handleTeamRemove = this.handleTeamRemove.bind(this);
+    this.handleTeamEditing = this.handleTeamEditing.bind(this);
+  }
+
   handleTeamRemove() {
     this.props.onTeamRemove();
   }