title: Flutter Material icons: some icons dont exist in the flutter's Icons class
body: <p>I realize that this is a duplicate of <a href="https://stackoverflow.com/q/68818470/12555423">this question</a>, but that question does not seem to have any activity so I'm trying to get more attention to this issue.</p>
  <p>I am trying to use the <code>percent</code> icon from Material icons, although in the fonts.google.com site,it shows flutter implementation (screenshot attached below), when I try to call it from flutter code I get the error <code>The getter 'percent' isn't defined for the type 'Icons'.</code> (screenshot attached below).</p>
  <p>what is the reason for this, and why is google trying to show some icon is supported for flutter when it clearly is not?</p>
  <p><a href="https://i.stack.imgur.com/T3Pv8.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/T3Pv8.png" alt="fonts.google.com screenshot that shows that the icon is defined for flutter" /></a></p>
  <p><a href="https://i.stack.imgur.com/DkWdn.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/DkWdn.png" alt="vsc screenshot that shows the error occurring when trying to call the percent icon" /></a></p>
  <p>here is my <code>flutter doctor -v</code> output:</p>
  <pre><code>[√] Flutter (Channel stable, 2.8.0, on Microsoft Windows [Version 10.0.19041.1348], locale en-US)
      • Flutter version 2.8.0 at C:\Users\adnan\flutter
      • Upstream repository https://github.com/flutter/flutter.git
      • Framework revision cf44000065 (23 hours ago), 2021-12-08 14:06:50 -0800
      • Engine revision 40a99c5951
      • Dart version 2.15.0
      • Pub download mirror https://pub.flutter-io.cn
      • Flutter download mirror https://storage.flutter-io.cn
  
  [√] Android toolchain - develop for Android devices (Android SDK version 30.0.3)
      • Android SDK at C:\Users\adnan\AppData\Local\Android\sdk
      • Platform android-31, build-tools 30.0.3
      • Java binary at: C:\Program Files\Android\Android Studio1\jre\bin\java     
      • Java version OpenJDK Runtime Environment (build 11.0.10+0-b96-7249189)    
      • All Android licenses accepted.
  
  [√] Chrome - develop for the web
      • Chrome at C:\Program Files\Google\Chrome\Application\chrome.exe
  
  [√] Android Studio (version 2020.3)
      • Android Studio at C:\Program Files\Android\Android Studio1
      • 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 11.0.10+0-b96-7249189)
  
  [!] Android Studio (version 4.1)
      • Android Studio at C:\Program Files\Android\Android Studio
      • 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
      X Unable to determine bundled Java version.
      • Try updating or re-installing Android Studio.
  
  [√] VS Code (version 1.62.3)
      • VS Code at C:\Users\adnan\AppData\Local\Programs\Microsoft VS Code
      • Flutter extension version 3.29.0
  
  [√] VS Code (version 1.61.0-insider)
      • VS Code at C:\Users\adnan\AppData\Local\Programs\Microsoft VS Code Insiders
      • Flutter extension can be installed from:
         https://marketplace.visualstudio.com/items?itemName=Dart-Code.flutter
  
  [√] Connected device (3 available)
      • sdk gphone x86 (mobile) • emulator-5554 • android-x86    • Android 11 (API 30) (emulator)
      • Chrome (web)            • chrome        • web-javascript • Google Chrome 96.0.4664.45
      • Edge (web)              • edge          • web-javascript • Microsoft Edge 96.0.1054.43
  
  ! Doctor found issues in 1 category.
  </code></pre>