Picker - fix migrated picker with renderPicker (#1628)

(cherry picked from commit 6fe8835)

Author: M-i-k-e-l

src/components/picker/index.js

@@ -434,7 +434,7 @@ class Picker extends Component {
       return (
         <View left>
           <Button {...customPickerProps} link onPress={this.handlePickerOnPress} testID={testID}>
-            {renderPicker(value)}
+            {renderPicker(value, this.getLabel(value))}
           </Button>
           {this.renderExpandableModal()}
         </View>

typings/components/Picker.d.ts

@@ -46,7 +46,7 @@ export interface PickerProps extends Omit<TextFieldProps, 'value'> {
   onChange?: (value: PickerItemValue) => void;
   mode?: PickerMode;
   enableModalBlur?: boolean;
-  renderPicker?: (value?: PickerItemValue) => ReactElement | ReactElement[];
+  renderPicker?: (value?: PickerItemValue, label?: string) => ReactElement | ReactElement[];
   renderItem?: PickerItemRenderItemFunc;
   renderCustomModal?: (modalProps: object) => ReactElement | ReactElement[];
   customPickerProps?: object;