Divide <Workspace/> into component and container (part of #1727).

__tests__/src/components/Workspace.test.js

 import React from 'react';
 import { shallow } from 'enzyme';
-import { Workspace } from '../../../src/components/Workspace';
+import Workspace from '../../../src/components/Workspace';
 import ConnectedWindow from '../../../src/components/Window';
 
 describe('Workspace', () => {

src/components/App.js

@@ -3,7 +3,7 @@ import PropTypes from 'prop-types';
 import CssBaseline from '@material-ui/core/CssBaseline';
 import Fullscreen from 'react-fullscreen-crossbrowser';
 import WorkspaceControlPanel from './WorkspaceControlPanel';
-import ConnectedWorkspace from './Workspace';
+import Workspace from '../containers/Workspace';
 import ns from '../config/css-ns';
 
 /**
@@ -24,7 +24,7 @@ class App extends Component {
           enabled={workspace.fullscreen}
           onChange={isFullscreenEnabled => fullscreenWorkspace(isFullscreenEnabled)}
         >
-          <ConnectedWorkspace />
+          <Workspace />
         </Fullscreen>
         <WorkspaceControlPanel />
       </div>

src/components/Workspace.js

 import React from 'react';
-import { compose } from 'redux';
-import { connect } from 'react-redux';
 import PropTypes from 'prop-types';
 import ConnectedWindow from './Window';
 import ns from '../config/css-ns';
@@ -10,7 +8,7 @@ import ns from '../config/css-ns';
  * @memberof Workspace
  * @private
  */
-export class Workspace extends React.Component {
+class Workspace extends React.Component {
   /**
    * render
    */
@@ -35,20 +33,4 @@ Workspace.propTypes = {
   windows: PropTypes.object.isRequired, // eslint-disable-line react/forbid-prop-types
 };
 
-/**
- * mapStateToProps - to hook up connect
- * @memberof Workspace
- * @private
- */
-const mapStateToProps = state => (
-  {
-    windows: state.windows,
-  }
-);
-
-const enhance = compose(
-  connect(mapStateToProps),
-  // further HOC go here
-);
-
-export default enhance(Workspace);
+export default Workspace;

src/containers/Workspace.js

+import { compose } from 'redux';
+import { connect } from 'react-redux';
+import Workspace from '../components/Workspace';
+
+/**
+ * mapStateToProps - to hook up connect
+ * @memberof Workspace
+ * @private
+ */
+const mapStateToProps = state => (
+  {
+    windows: state.windows,
+  }
+);
+
+const enhance = compose(
+  connect(mapStateToProps),
+  // further HOC go here
+);
+
+export default enhance(Workspace);