title: Error: Required named parameter 'vsync' must be provided
body: <p>I run project and I don't edit anything on it then it throw this exception</p>
  <pre><code>/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/getwidget-2.0.5/lib/components/animation/gf_animation.dart:244:28: Error: Required named parameter 'vsync' must be provided.
          child: AnimatedSize(
                             ^
  /C:/src/flutter/packages/flutter/lib/src/widgets/animated_size.dart:56:9: Context: Found this candidate, but the arguments don't match.
    const AnimatedSize({
          ^^^^^^^^^^^^
  
  
  FAILURE: Build failed with an exception.
  
  * Where:
  Script 'C:\src\flutter\packages\flutter_tools\gradle\flutter.gradle' line: 1035
  
  * What went wrong:
  Execution failed for task ':app:compileFlutterBuildDebug'.
  &gt; Process 'command 'C:\src\flutter\bin\flutter.bat'' finished with non-zero exit value 1
  
  * Try:
  Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
  
  * Get more help at https://help.gradle.org
  
  BUILD FAILED in 32s
  Exception: Gradle task assembleDebug failed with exit code 1
  </code></pre>
  <p>How fix this error to run project please help me and thank you</p>