Fix embed view=split (codesandbox#615)

Author: CompuIves

packages/app/src/embed/components/App/index.js

@@ -56,6 +56,7 @@ export default class App extends React.PureComponent<{}, State> {
       isInProjectView,
       isPreviewScreen,
       isEditorScreen,
+      isSplitScreen,
       autoResize,
       hideNavigation,
       fontSize,
@@ -73,8 +74,8 @@ export default class App extends React.PureComponent<{}, State> {
       notFound: false,
       sandbox: null,
       fontSize: fontSize || 16,
-      showEditor: isEditorScreen,
-      showPreview: isPreviewScreen,
+      showEditor: isSplitScreen || isEditorScreen,
+      showPreview: isSplitScreen || isPreviewScreen,
       isInProjectView,
       currentModule,
       initialPath,