title: This.props returning undefined?
body: <p>I'm currently passing data into my component via props, and for some reason it's showing up as undefined. 
  From my parent component perspective I have the following pass 2 props, <code>data</code> and <code>header</code>. </p>
  
  <pre><code>class ContractTable extends Component {
  constructor(props) {
      super(props);
      this.state = {
          data: []
      };
  }
  
  render() {
      return (
          &lt;div&gt;
              &lt;p&gt;&lt;/p&gt;
              &lt;MuiThemeProvider&gt;
                  &lt;TableTest
                      data={this.state.data}
                      header={[
                          {
                              name: "First Name",
                              prop: "firstName"
                          },
                          {
                              name: "Last Name",
                              prop: "lastName"
                          },
                          {
                              name: "Age",
                              prop: "age"
                          },
                          {
                              name: "Height",
                              prop: "height"
                          },
                          {
                              name: "Address",
                              prop: "address"
                          }
                      ]}
                  /&gt;
              &lt;/MuiThemeProvider&gt;
              &lt;p&gt;&lt;/p&gt;
          &lt;/div&gt;
      );
  }
  </code></pre>
  
  <p>I try to grab the props and set it as my state, but when I log <code>this.props.data</code> or <code>this.props.header</code> it returns undefined. Why is this? </p>
  
  <pre><code>import React, { Component } from 'react';
  import {
  Table,
  TableBody,
  TableHeader,
  TableHeaderColumn,
  TableRow,
  TableRowColumn,
  } from 'material-ui/Table';
  
  class TableTest extends Component {
  constructor(props) {
      super(props);
  
      this.state = {
          data: props.data,
          header: props.header
      }
  
      this.row = this.row.bind(this);
  }
  
  row = (currentValue, index, header) =&gt; (
      &lt;TableRow key={`t-${index}`}&gt;
          {
              header.map((headerName, index) =&gt; (
                  &lt;TableRowColumn key={`trc-${index}`}&gt;
                      {currentValue[headerName.prop]}
                  &lt;/TableRowColumn&gt;
              ))
          }
      &lt;/TableRow&gt;
  );
  
  render() {
      return 'hello'
  }
  }
  
  export default TableTest;
  </code></pre>