title: Change actionOverflowButtonStyle with appcompat v21
body: <p>I want to change the action overflow button icon in my <code>Toolbar</code> (or <code>ActionBar</code>, not matter).</p>
  
  <p>So I go this way:</p>
  
  <pre><code>&lt;style name="AppTheme.Base" parent="Theme.AppCompat.Light.NoActionBar"&gt;
      &lt;item name="android:actionOverflowButtonStyle"&gt;@style/AppTheme.OverflowButtonStyle&lt;/item&gt;
  &lt;/style&gt;
  
  &lt;style name="AppTheme.OverflowButtonStyle" parent="Widget.AppCompat.Light.ActionButton.Overflow"&gt;
      &lt;item name="android:src"&gt;@drawable/ic_custom&lt;/item&gt;
  &lt;/style&gt;
  </code></pre>
  
  <p>or this way:</p>
  
  <pre><code>&lt;style name="AppTheme.Base" parent="Theme.AppCompat.Light.NoActionBar"&gt;
      &lt;item name="toolbarStyle"&gt;@style/AppTheme.ToolbarStyle&lt;/item&gt;
  &lt;/style&gt;
  
  &lt;style name="AppTheme.ToolbarStyle" parent="Base.Widget.AppCompat.Toolbar"&gt;
      &lt;item name="actionOverflowButtonStyle"&gt;@style/AppTheme.OverflowButtonStyle&lt;/item&gt;
  &lt;/style&gt;
  
  &lt;style name="AppTheme.OverflowButtonStyle" parent="Widget.AppCompat.Light.ActionButton.Overflow"&gt;
      &lt;item name="android:src"&gt;@drawable/ic_custom&lt;/item&gt;
  &lt;/style&gt;
  </code></pre>
  
  <p>But both ways don't work. What's wrong there? </p>
  
  <p>And the second question is can I change one resourse from library to another resource from library (I just want to change black action overflow button to white, which presents in the library too). </p>