Flutter: O comportamento do GestureDetector depende da propriedade interna do Container

Passos para reproduzir

Existem dois GestureDetectors que incluem um contêiner com preenchimento,
a única diferença é se o Container interno tem propriedade de cor ou não.

Toque no espaço ao redor dos ícones, ou seja, toque na área de preenchimento:

• O contêiner tem cor: onTap é chamado
• O contêiner não tem cor: onTap não é chamado

import 'package:flutter/foundation.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter/material.dart';

void main() {
  final GlobalKey<ScaffoldState> _key = new GlobalKey<ScaffoldState>();
  runApp(new MaterialApp(
    title: 'GestureDetector Test',
    home: new Builder(builder: (BuildContext context) {
      return new Scaffold(
        key: _key,
        appBar: new AppBar(title: new Text("GestureDetector Test")),
        body: new Column(
          children: <Widget>[
            new Container(
              child: new GestureDetector(
                onTap: () {
                  _key.currentState.showSnackBar(new SnackBar(content: new Text("Foo!")));
                },
                child: new Container(
                  color: Colors.blue,
                  padding: const EdgeInsets.all(16.0),
                  child: const Icon(Icons.star, size: 32.0),
                ),
              )
            ),
            new Container(
              child: new GestureDetector(
                onTap: () {
                  _key.currentState.showSnackBar(new SnackBar(content: new Text("Bar!")));
                },
                child: new Container(
                  //color: Colors.blue, // no color
                  padding: const EdgeInsets.all(16.0),
                  child: const Icon(Icons.star, size: 32.0),
                ),
              )
            ),
          ],
        ),
      );
    }),
  ));
}

Toque no próprio ícone, ambos onTap serão chamados.

Flutter Doctor

alfa 0.0.20

[✓] Flutter (on Mac OS X 10.12.6 16G1114, locale ja-JP, channel alpha)
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    • Platform android-27, build-tools 27.0.3
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    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b08)

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