title: FAB with anchor in coordinator layout has extra margin in android pre-lollipop
body: <p>I have a <code>CoordinatroLayout</code>with <code>FloatingActionButton</code>. Here is my code:</p>
  
  <pre><code>&lt;android.support.design.widget.CoordinatorLayout
          xmlns:android="http://schemas.android.com/apk/res/android"
          xmlns:app="http://schemas.android.com/apk/res-auto"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:layout_below="@+id/toolbar_layout"
          android:layout_above="@+id/actionbar"&gt;
  
          &lt;LinearLayout
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:orientation="vertical"&gt;
  
              &lt;android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
                  android:id="@+id/toolbar"
                  android:layout_width="match_parent"
                  android:layout_height="120dp"
                  android:minHeight="?android:attr/actionBarSize"
                  android:background="@color/toolbar_color" /&gt;
  
  
              &lt;ScrollView
                  android:layout_width="match_parent"
                  android:layout_height="wrap_content"
  
                  &gt;
  
              &lt;/ScrollView&gt;
  
  
          &lt;/LinearLayout&gt;
  
          &lt;android.support.design.widget.FloatingActionButton
              android:id="@+id/fab"
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
  
              android:clickable="true"
              app:fabSize="mini"
              android:src="@mipmap/ic_action_edit"
              app:layout_anchor="@id/toolbar"
              app:layout_anchorGravity="bottom|right|end"
              app:backgroundTint="@color/toolbar_color"            /&gt;
          &lt;/android.support.design.widget.CoordinatorLayout&gt;
  </code></pre>
  
  <p>But it appears differently in lollipop and pre-lollipop devices.</p>
  
  <p>Lollipop:</p>
  
  <p><a href="https://i.stack.imgur.com/eugvl.png" rel="noreferrer"><img src="https://i.stack.imgur.com/eugvl.png" alt="enter image description here"></a></p>
  
  <p>Pre-Lollipop:
  <a href="https://i.stack.imgur.com/a0TOY.png" rel="noreferrer"><img src="https://i.stack.imgur.com/a0TOY.png" alt="enter image description here"></a></p>
  
  <p>Actually I haven't add any margin. But FAB has margin in pre-lollipop devices.</p>
  
  <p>I have also seen this problem in <a href="https://github.com/chrisbanes/cheesesquare" rel="noreferrer">cheessesquare</a> sample. It shows different margins too. What is the problem?</p>