title: Margins on children of ConstraintLayout do not display?
body: <p>I'm using Android's new ConstraintLayout for my app and I've been having problems having margins on elements show up. For reference I'm using the following line in my gradle file for ConstraintLayout <code>com.android.support.constraint:constraint-layout:1.0.0-beta4</code>. The code in my layout is below.</p>
  
  <pre><code>&lt;android.support.constraint.ConstraintLayout
      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="wrap_content"
      android:paddingStart="@dimen/activity_horizontal_margin"
      android:paddingLeft="@dimen/activity_horizontal_margin"
      android:paddingTop="@dimen/post_vertical_padding"
      android:paddingEnd="@dimen/activity_horizontal_margin"
      android:paddingRight="@dimen/activity_horizontal_margin"
      android:paddingBottom="@dimen/post_vertical_padding"
      android:background="?android:attr/selectableItemBackground"&gt;
  
      &lt;TextView
          style="@style/TitleText"
          android:id="@+id/post_type"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_marginBottom="@dimen/post_line_vertical_padding"
          android:layout_marginEnd="@dimen/post_type_horizontal_padding"
          android:layout_marginRight="@dimen/post_type_horizontal_padding"
          app:layout_constraintLeft_toRightOf="@id/poster_profile_pic"
          app:layout_constraintTop_toTopOf="parent" /&gt;
  
      &lt;TextView
          android:id="@+id/poster_name"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          app:layout_constraintLeft_toRightOf="@id/post_type"
          app:layout_constraintBaseline_toBaselineOf="@id/post_type" /&gt;
  
  &lt;/android.support.constraint.ConstraintLayout&gt;
  </code></pre>