Repository: flutter
Issue: Android App Launch does not use theme properly
Labels: c: new feature,platform-android,framework,engine,f: material design,a: fidelity,has reproducible steps,P2,found in release: 3.3,found in release: 3.7,team-android,triaged-android

**Short Summary of issue**
It seems that the app launch process does not handle themes properly and does not theme the status bar and background color correctly per how you would expect if you were developing natively on Android

**Additonal Details**
So from my testing there is two basic app launch scenarios a native app should use to launch the app per the material documentation:
https://material.io/design/communication/launch-screen.html#usage
Basically a splash screen and placeholder UI.  I saw there are are many pull requests related to this such as:
https://github.com/flutter/flutter/issues/8147
https://github.com/flutter/flutter/pull/11505

It seems that on iOS it works how I would expect but on Android I would expect it to use the theme on launch to make it feel more native.

**Below is how it works on Native Android:**
_Android Native With Splash_
Note: Shows status bar per the theme.
![androidnativewithsplash](https://user-images.githubusercontent.com/957870/47063479-c121f200-d1a0-11e8-8be1-917f98491ba9.gif)
_Android Native Without Splash:_
Note: Shows status bar per the theme.
![androidwithoutsplash](https://user-images.githubusercontent.com/957870/47063507-e282de00-d1a0-11e8-9f08-09c1480c4737.gif)

**Steps to reproduce**
If I create the default flutter android application per Android Studio and below is my flutter doctor results
```
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel beta, v0.9.4, on Mac OS X 10.14 18A391, locale en-US)
[✓] Android toolchain - develop for Android devices (Android SDK 28.0.3)
[✓] iOS toolchain - develop for iOS devices (Xcode 10.0)
[✓] Android Studio (version 3.2)
[✓] VS Code (version 1.28.1)
[✓] Connected devices (1 available)
```

I am testing on a Pixel 2 Emulator API 26

There are 3 situations I would like to highlight with examples
1) Default flutter app with no modifications looks like below:
Note: Status bar changes from Black to the themed blue
![flutterdefaultproject](https://user-images.githubusercontent.com/957870/47063681-ccc1e880-d1a1-11e8-9414-8a8e17532535.gif)

2) Flutter app with splash modified to match theme color
Note: Status bar changes from Black to themed blue
![flutterandroidsplash](https://user-images.githubusercontent.com/957870/47063723-085cb280-d1a2-11e8-9e0f-dfaf07d84c19.gif)

3) Flutter app with splash disabled
Note: Screen is black and then goes into themed app
![flutterandroidnosplash](https://user-images.githubusercontent.com/957870/47063763-41952280-d1a2-11e8-8962-335dc556b314.gif)

**Goal state**
It would be great if there was a way to first of all get the theme you choose in flutter to plug into android like you included it via a style.  Also with the solution you might want to consider how to support more placeholder UI such as I want to show the toolbar on app launch or something like that. 

**Work around**
https://github.com/DavidCorrado/FlutterSplashTesting/commit/9aa6861e64fffe52d0138e19ce7be79ed75caaed