From build log:
```
../../flutter/shell/platform/android/io/flutter/view/FlutterView.java:95: error: cannot find symbol
private final LocalizationChannel localizationChannel;
^
symbol: class LocalizationChannel
location: class FlutterView
../../flutter/shell/platform/android/io/flutter/view/FlutterView.java:172: error: cannot find symbol
localizationChannel = new LocalizationChannel(dartExecutor);
^
symbol: class LocalizationChannel
location: class FlutterView
2 errors
```
This reverts commit 256db4bc23.
After bumping the targetSdk of Flutter apps to 28, the keyboard doesn't open anymore when inputting text on an Android Pie devices. The problem is caused by a change on the way the focus in handled: when the call `mImm.showSoftInput(view, 0);` is made, the currently focused view is the `DecorView` from the `Activity` hosting Flutter but the passed view reference (`view` argument) is the `FlutterView`. As the `InputMethodManager` checks if both views are the same before showing the keyboard, it never appears because the `FlutterView` never has focus.
As Flutter doesn't have any input views as far as the Android side is concerned, the focus should always stay on the `FlutterView` itself and thus, this PR changes the `TextInputPlugin` to focus on the `FlutterView` as soon as it's created, fixing the keyboard issue.
Co-authored-by: Igor Borges <igorborges12@gmail.com>
Decouple PlatformViewsController from FlutterView.
Instead of getting a FlutterView instance, depend on the specific interfaces required by
PlatformViewsController (BinaryMessenger, TextureRegistry, and Context).
This allows using PlatformViewsControlling in the flutter/embedding
code.