change navigation.toggleDrawer to goBack()?

[todo]

mobile/screens/WebviewScreen.js

Lines 10 to 15 in d9a8c5d

	// TODO: change navigation.toggleDrawer to goBack()?
	class WebviewScreen extends React.Component {
	render() {
	return (
	<View style={styles.container}>
	<Appbar.Header>

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This issue was generated by todo based on a TODO comment in d9a8c5d. It's been assigned to @kylebarron because they committed the code.