title: Tabs in TabLayout not filling up entire ActionBar
body: <p>I am using a <code>TabLayout</code> and <code>ViewPager</code> to display <code>ActionBar tabs</code> following the guide <a href="https://guides.codepath.com/android/Google-Play-Style-Tabs-using-TabLayout" rel="noreferrer">Google Play Style Tabs using TabLayout</a>, however my tabs are squished to the left side of the ActionBar, shown below:</p>
  
  <p><img src="https://i.stack.imgur.com/lAaZh.png" width="320" height="500"><br>
  And I would like them to take up the whole bar with equal widths. I've made only a few minor changes to the guide: </p>
  
  <p>In activity_main.xml a style was created to show the ActionBar:</p>
  
  <pre><code>&lt;android.support.design.widget.TabLayout
    android:id="@+id/sliding_tabs"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    style="@style/AppTheme"
    app:tabMode="scrollable" /&gt;
  </code></pre>
  
  <p>Here is the styles.xml code:</p>
  
  <pre><code>&lt;style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar"&gt;
    &lt;item name="windowActionBar"&gt;true&lt;/item&gt;
    &lt;item name="tabIndicatorColor"&gt;#ffff0030&lt;/item&gt;
  &lt;/style&gt;
  </code></pre>
  
  <p>Also, my <code>MainActivity</code> now extends <code>AppCompatActivity</code> instead of a <code>FragmentActivity</code>.</p>