运行 flutter doctor 的时候出现 Android Studio (not installed)
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel beta, v1.1.8, on Mac OS X 10.13.6 17G4015, locale en-US)
[✓] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[✓] iOS toolchain - develop for iOS devices (Xcode 10.1)
[!] Android Studio (not installed)
[✓] IntelliJ IDEA Ultimate Edition (version 2018.3.3)
[✓] Connected device (1 available) ! Doctor found issues in 1 category.
window 系统上的解决方案(前提已经安装了 android studio)：
flutter config --android-studio-dir <path to android studio. Default: "c:\program files\android\android studio">
