Build failure using image_picker

image_picker.dart

import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
          child: RaisedButton(
        child: Text('Tap'),
        onPressed: () {
          _selectOptions();
        },
      )),
    );
  }

  Future<void> _selectOptions() {
    return showDialog(
        context: context,
        builder: (BuildContext context) {
          return AlertDialog(
            content: new SingleChildScrollView(
              child: new ListBody(
                children: <Widget>[
                  GestureDetector(
                    child: new Text('Take a picture'),
                    onTap: openCamera,
                  ),
                  Padding(
                    padding: EdgeInsets.all(8.0),
                  ),
                  GestureDetector(
                    child: new Text('Select from gallery'),
                    onTap: openGallery,
                  ),
                ],
              ),
            ),
          );
        });
  }

  void openCamera() async {
    var picture = await ImagePicker.pickImage(
      source: ImageSource.camera,
    );
  }

  void openGallery() async {
    var gallery = await ImagePicker.pickImage(
      source: ImageSource.gallery,
    );
  }
}

I am unable to replicate the build failure when image_picker plugin is used. I tried a sample code using latest version of image_picker (^0.6.7+1) and flutter stable version v1.17.2 and it seems to be working fine with no issues. I am able to open camera and gallery using the plugin.

Issue - flutter/flutter#49039