title: Dart version is 2.2.0 but I get an error requiring version >=2.2.0
body: <p>I have the latest version of Flutter and I'm trying to run the official Flutter gallery app. When I do <code>dart --version</code> I get </p>
  
  <pre><code>Dart VM version: 2.2.0 (Tue Feb 26 15:04:32 2019 +0100) on "macos_x64"
  </code></pre>
  
  <p>However, when I try to get the packages: </p>
  
  <pre><code>[flutter_gallery] flutter packages get
  Running "flutter packages get" in flutter_gallery...            
  The current Dart SDK version is 2.1.2-dev.0.0.flutter-0a7dcf17eb.
  
  Because flutter_gallery requires SDK version &gt;=2.2.0 &lt;3.0.0, version solving failed.
  pub get failed (1)
  exit code 1
  </code></pre>
  
  <p>What's interesting is when I run <code>flutter upgrade</code> it lists an older version of Dart (Tools).</p>
  
  <pre><code>Upgrading Flutter from /Users/leejohnson/dev/flutter...
  From https://github.com/flutter/flutter
     a1bee54fd..59ce7d6bf  dev        -&gt; origin/dev
     55a2ee588..f8f2b043e  master     -&gt; origin/master
   * [new tag]             v1.3.13    -&gt; v1.3.13
  Already up to date.
  
  Upgrading engine...
  Already up-to-date.
  
  Flutter 1.2.1 • channel stable • https://github.com/flutter/flutter.git
  Framework • revision 8661d8aecd (5 weeks ago) • 2019-02-14 19:19:53 -0800
  Engine • revision 3757390fa4
  Tools • Dart 2.1.2 (build 2.1.2-dev.0.0 0a7dcf17eb)
  </code></pre>
  
  <p>If I understand this error correctly, Flutter is not using the latest version of Dart yet the official Flutter example app requires it. How do I fix this?</p>