title: WebView in CoordinatorLayout with CollapsingToolbarLayout
body: <p>I'd like to add a WebView in a CoordinatorLayout, having CollapsingToolbarLayout in AppBarLayout.
  The problem is that WebView shrinks in height and doesn't fill the space below the toolbar, making it not usable. 
  I tried also to use WebView as child of NestedScrollView: initially it doesn't work (it shrinks my WebView in height), but scrolling my shrinked WebView makes it fill viewport.</p>
  
  <p>Here is the layout I used:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;android.support.design.widget.CoordinatorLayout
      android:id="@+id/main_content"
      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"
      android:fitsSystemWindows="true"&gt;
  
      &lt;android.support.design.widget.AppBarLayout
          android:id="@+id/appbar"
          android:layout_width="match_parent"
          android:layout_height="256dp"
          android:fitsSystemWindows="true"
          android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"&gt;
  
          &lt;android.support.design.widget.CollapsingToolbarLayout
              android:id="@+id/collapsing_toolbar"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              android:fitsSystemWindows="true"
              app:contentScrim="?attr/colorPrimary"
              app:expandedTitleMarginEnd="64dp"
              app:expandedTitleMarginStart="48dp"
              app:layout_scrollFlags="scroll|exitUntilCollapsed"&gt;
  
              &lt;ImageView
                  android:id="@+id/backdrop"
                  android:layout_width="match_parent"
                  android:layout_height="match_parent"
                  android:fitsSystemWindows="true"
                  android:scaleType="centerCrop"
                  app:layout_collapseMode="parallax" /&gt;
  
              &lt;android.support.v7.widget.Toolbar
                  android:id="@+id/toolbar"
                  android:layout_width="match_parent"
                  android:layout_height="?attr/actionBarSize"
                  app:layout_collapseMode="pin"
                  app:popupTheme="@style/ThemeOverlay.AppCompat.Light" /&gt;
  
          &lt;/android.support.design.widget.CollapsingToolbarLayout&gt;
  
      &lt;/android.support.design.widget.AppBarLayout&gt;
  
      &lt;android.support.v4.widget.NestedScrollView
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          app:layout_behavior="@string/appbar_scrolling_view_behavior"&gt;
  
          &lt;WebView
              android:id="@+id/article"
              android:layout_width="match_parent"
              android:layout_height="match_parent" /&gt;
      &lt;/android.support.v4.widget.NestedScrollView&gt;
  &lt;/android.support.design.widget.CoordinatorLayout&gt;
  </code></pre>