navigation.goBack(null) and fix SearchBar cancelButtonText (#1)

* navigation.goBack(null)

Add null parameter, If null parameter is not present it won't go back when the Search Screen is a part of a top-level Navigator.

* Fix SearchBar cancelButtonText

* Fix HeaderBackButton import

HeaderBackButton has been moved to react-navigation-stack

Author: tomsotte

src/Header.js

@@ -7,7 +7,8 @@ import {
   StyleSheet,
   View,
 } from 'react-native';
-import { withNavigation, HeaderBackButton } from 'react-navigation';
+import { withNavigation } from 'react-navigation';
+import { HeaderBackButton } from 'react-navigation-stack';
 import { getInset, getStatusBarHeight } from 'react-native-safe-area-view';
 import { isIphoneX } from 'react-native-iphone-x-helper';
 

src/SearchBar.ios.js

@@ -178,7 +178,7 @@ export default class SearchBar extends React.PureComponent {
     if (this.props.onCancelPress) {
       this.props.onCancelPress(this.props.navigation.goBack);
     } else {
-      this.props.navigation.goBack();
+      this.props.navigation.goBack(null);
     }
   };
 }

src/SearchLayout.js

@@ -50,6 +50,7 @@ export default class SearchLayout extends React.Component {
             tintColor={
               this.props.searchInputTintColor || this.props.headerTintColor
             }
+            cancelButtonText={this.props.cancelButtonText}
           />
         </Header>