title: Android NestedScrollView scroll does not work
body: <p>Title pretty much says it all. 
  I have an Activity with a FrameLayout and I add a fragment at runtime. Data from the fragment are being displayed ok but I cant scroll.</p>
  
  <p>The Activity's layout is :</p>
  
  <pre><code>    &lt;RelativeLayout android:id="@+id/content_layout" 
   xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent" android:layout_height="match_parent"
  tools:context=".MainActivity"&gt;
  
      &lt;android.support.design.widget.CoordinatorLayout
          android:fitsSystemWindows="true"
          android:layout_width="match_parent"
          android:layout_height="match_parent"&gt;
  
          &lt;android.support.design.widget.AppBarLayout
              android:layout_width="match_parent"
              android:layout_height="wrap_content"&gt;
  
              &lt;android.support.design.widget.CollapsingToolbarLayout
                  android:id="@+id/collapsingToolbarLayout"
                  android:layout_width="match_parent"
                  android:layout_height="match_parent"
                  app:layout_scrollFlags="scroll|exitUntilCollapsed"&gt;
  
                  &lt;android.support.v7.widget.Toolbar
                      android:id="@+id/toolbar"
                      android:layout_width="match_parent" android:layout_height="?attr/actionBarSize"
                      android:background="?attr/colorPrimary" app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
                      app:layout_scrollFlags="scroll|enterAlways" /&gt;
  
              &lt;/android.support.design.widget.CollapsingToolbarLayout&gt;
  
          &lt;/android.support.design.widget.AppBarLayout&gt;
  
          &lt;FrameLayout android:id="@+id/fl_content" android:layout_below="@id/toolbar"
              android:layout_width="match_parent" android:layout_height="match_parent"
              app:layout_behavior="@string/appbar_scrolling_view_behavior" &gt;
  
              &lt;android.support.v4.widget.NestedScrollView
                  android:layout_width="match_parent" android:layout_height="match_parent"/&gt;
  
          &lt;/FrameLayout&gt;
  
      &lt;/android.support.design.widget.CoordinatorLayout&gt;
  
  &lt;/RelativeLayout&gt;
  </code></pre>
  
  <p>and the fragment's layout is :</p>
  
  <pre><code>&lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical"
  android:layout_width="match_parent" android:layout_height="match_parent"&gt;
  
  &lt;ImageView android:id="@+id/iv_cover"
      android:layout_width="100dp" android:layout_height="100dp" /&gt;
  
  &lt;TextView android:id="@+id/tv_release_artistname"
      android:layout_width="wrap_content" android:layout_height="wrap_content" /&gt;
  
  &lt;TextView android:id="@+id/tv_release_albumname"
      android:layout_width="wrap_content" android:layout_height="wrap_content" /&gt;
  
  &lt;TextView android:id="@+id/tv_release_year"
      android:layout_width="wrap_content" android:layout_height="wrap_content" /&gt;
  
  &lt;TextView android:id="@+id/tv_release_label"
      android:layout_width="wrap_content" android:layout_height="wrap_content" /&gt;
  
  &lt;TextView android:id="@+id/tv_release_style"
      android:layout_width="wrap_content" android:layout_height="wrap_content" /&gt;
  
  &lt;TextView android:id="@+id/tv_release_notes"
      android:layout_width="wrap_content" android:layout_height="wrap_content" /&gt;
  </code></pre>
  
  <p></p>