title: Android centre title with navigation drawer
body: <p>I currently have a navigation drawer with a toolbar that has a title, i wish to centre this title within the toolbar but the toolbar does not seem to take into consideration the drawer icon as you can see in the following picture.</p>
  
  <p><a href="https://i.stack.imgur.com/I1UkA.png" rel="noreferrer"><img src="https://i.stack.imgur.com/I1UkA.png" alt="Off centre"></a></p>
  
  <p>whereas when i use the same toolbar layout for other activities that are not inside the navigation drawer the title is centred perfectly, as show in this picture:</p>
  
  <p><a href="https://i.stack.imgur.com/v0ntn.png" rel="noreferrer"><img src="https://i.stack.imgur.com/v0ntn.png" alt="enter image description here"></a></p>
  
  <p>So how do i get it to take into account this icon?</p>
  
  <p>Here is my layout:</p>
  
  <pre><code>&lt;android.support.design.widget.AppBarLayout
      xmlns:app="http://schemas.android.com/apk/res-auto"
      xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_height="wrap_content"
      android:layout_width="match_parent"
      android:theme="@style/Theme.App.AppBarOverlay"&gt;
  
      &lt;android.support.v7.widget.Toolbar
          android:id="@+id/toolbar"
          android:layout_width="match_parent"
          android:layout_height="?attr/actionBarSize"
          android:background="@color/black"
          app:popupTheme="@style/Theme.App.PopupOverlay"&gt;
  
          &lt;RelativeLayout
              android:layout_width="match_parent"
              android:layout_height="wrap_content"&gt;
  
              &lt;TextView
                  android:id="@+id/toolbar_title"
                  android:layout_width="wrap_content"
                  android:layout_height="wrap_content"
                  android:layout_centerInParent="true"
                  android:textColor="@color/white"
                  android:textStyle="bold"
                  android:text="Title"
                  android:textSize="16sp" /&gt;
  
          &lt;/RelativeLayout&gt;
  
      &lt;/android.support.v7.widget.Toolbar&gt;
  
  &lt;/android.support.design.widget.AppBarLayout&gt;
  </code></pre>