title: Floating Action Button in wrong position
body: <p>I have Floating Action Buttons in two of my Fragment layouts and sometimes they move to the wrong position, altough I use CoordinatorLayout. </p>
  
  <p><a href="http://i.stack.imgur.com/wmXwx.png" rel="noreferrer">This is how it should look</a></p>
  
  <p><a href="http://i.stack.imgur.com/OVvdw.png" rel="noreferrer">This is how it somtetimes look when i open the Fragment</a></p>
  
  <p>This is the code of my fragment:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;android.support.design.widget.CoordinatorLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  xmlns:app="http://schemas.android.com/apk/res-auto"
  android:layout_width="match_parent"
  android:layout_height="match_parent"&gt;
  
  &lt;LinearLayout android:id="@+id/notes_layout"
      android:orientation="vertical"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      tools:context=".fragments.NotesFragment"&gt;
  
      &lt;android.support.v7.widget.RecyclerView
          android:id="@+id/notes_recycler_view"
          android:layout_width="match_parent"
          android:layout_height="match_parent"/&gt;
  
  &lt;/LinearLayout&gt;
  
  &lt;android.support.design.widget.FloatingActionButton
      android:id="@+id/new_note_button"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_margin="16dp"
      android:clickable="true"
      android:src="@drawable/ic_add_black_48dp"
      app:layout_anchor="@id/notes_layout"
      app:layout_anchorGravity="bottom|center"
      android:onClick="openNewNote"/&gt;
  
  &lt;/android.support.design.widget.CoordinatorLayout&gt;
  </code></pre>
  
  <p>Does anyone have an idea why the FAB sometimes move to the wrong position?</p>