title: Non-nullable instance field must be initialized
body: <pre class="lang-dart prettyprint-override"><code>class Foo {
    int count; // Error
    void bar() =&gt; count = 0;
  }
  </code></pre>
  <p>Why I'm seeing an error when I'am already initializing it in the <code>bar</code> method? I could understand this error if <code>count</code> was marked <code>final</code>.</p>