Repository: flutter
Issue: [Textfield] cannot use Japanese keyboard (ATOK) on Android 
Labels: a: text input,e: device-specific,platform-android,framework,a: internationalization,P2,team-android,triaged-android

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I use ATOK keyboard to input a Japanese character, but the previous character is forcibly deleted when the second key input.
The switching-keyboard key is disabled and I cannot switch to other keyboard.

## Steps to Reproduce

<!-- Please include full steps to reproduce so that we can reproduce the problem. -->

1. Focus password textfield and enable software keyboard [ATOK keyboard] <!-- (see "Code sample" section below) -->
2. Touch any key or the switching-keyboard key.

**Expected results:** <!-- what did you want to see? -->
- Can input any characters correctlly.
- Can change to other keyboard.

**Actual results:** <!-- what did you see? -->
-Occuring ons some Android device only. Currently, I'm facing this issue only on Fujitsu devices using [Super ATOK ULTIAS]. (I check on HUWEI P20Lite, SamSung A31, Samsung A21s work fine)
-The issues depend on the software keyboard.
<details>
<summary>Code sample</summary>

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```
TextField(
      textInputAction: isLastInput ? TextInputAction.done : TextInputAction.next,
      obscureText: obscureText,
      controller: controller,
      readOnly: !enabled,
      focusNode: !enabled ? AlwaysDisabledFocusNode() : null,
      onChanged: onChanged,
      textAlignVertical: TextAlignVertical.center,
      onSubmitted: (value) {
        onSubmitted?.call(value);
      },
      style: TextStyle(
          fontWeight: FontWeight.w700
      ),
      decoration: InputDecoration(
        isCollapsed: true,
        icon: Icon(
          icon,
        ),
        hintText: hintText,
        hintStyle: TextStyle(
          fontWeight: FontWeight.w400
        ),
        border: InputBorder.none,
      ),
      inputFormatters: inputFormatters,
    );
```

</details>

<details>
  <summary>Logs</summary>

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<!-- Finally, paste the output of running `flutter doctor -v` here. -->

```
[✓] Flutter (Channel stable, 2.5.3, on Mac OS X 10.15.7 19H524 darwin-x64, locale en-VN)
    • Flutter version 2.5.3 at /Users/TuanHwing/Desktop/Development/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 18116933e7 (6 days ago), 2021-10-15 10:46:35 -0700
    • Engine revision d3ea636dc5
    • Dart version 2.14.4

[!] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
    • Android SDK at /Users/TuanHwing/Library/Android/sdk
    ✗ cmdline-tools component is missing
      Run `path/to/sdkmanager --install "cmdline-tools;latest"`
      See https://developer.android.com/studio/command-line for more details.
    ✗ Android license status unknown.
      Run `flutter doctor --android-licenses` to accept the SDK licenses.
      See https://flutter.dev/docs/get-started/install/macos#android-setup for more details.

[✓] Xcode - develop for iOS and macOS
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 12.4, Build version 12D4e
    • CocoaPods version 1.10.0

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 4.1)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6915495)

[✓] Connected device (2 available)
    • ANE LX2J (mobile) • SCV7N18611000792 • android-arm64  • Android 9 (API 28)
    • Chrome (web)      • chrome           • web-javascript • Google Chrome 94.0.4606.81
```

</details>

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Video:

https://user-images.githubusercontent.com/26133672/148007045-227f57c3-6ce7-4769-86f3-7811fdadb93b.mov

Any solution for this problem? Hope to hear from you soon