Describe the bug

Back button in reply does not look good.
It takes status bar area of phone.

To switch channel run:

flutter channel master
flutter upgrade

Flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel master, 1.25.0-9.0.pre.43, on Microsoft Windows [Version 10.0.19042.685], locale en-US)
[√] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
[√] Visual Studio - develop for Windows (Visual Studio Community 2019 16.8.1)
[√] Android Studio (version 4.1.0)
[√] VS Code (version 1.52.0)
[√] Connected device (2 available)

• No issues found!

To Reproduce
Steps to reproduce the behavior:

1. Go to 'Reply'

Screenshots

Smartphone (please complete the following information):

• Device: [e.g. Oneplus 7 pro]
• OS: [e.g. Android 10]

Additional context
I think back button should be implemented inside appbar so that it will not show in status bar area plus we will also be able to show title of page .