title: ForEach inside ScrollView doesn't take whole width
body: <p>I'm trying to re-create UI of my current app using SwiftUI. And it is way more difficult than I initially though. 
  I wanted to achieve card-like cells with some background behind them. I found that <code>List</code> doesn't support that, at least yet. <code>List</code> is so limited - it doesn't allow you to remove cell separator. </p>
  
  <p>So I moved to <code>ForEach</code> inside <code>ScrollView</code>. I guess that isn't something which should be used in production for long tables but that should work for now. The problem I have is that <code>ForeEach</code> view doesn't take all the width <code>ScrollView</code> provides. I can set <code>.frame(...)</code> modifier but that will require hardcoding width which I definitely don't want to do. </p>
  
  <p>Any ideas how to force <code>VStack</code> take full width of the ScrollView? I tried to use <code>ForeEach</code> without <code>VStack</code> and it has the same issue. It seems like <code>ScrollView</code> (parent view) "tells" its child view (VStack) that its frame is less that actual <code>ScrollView</code>'s frame. And based on that information child views build their layout and sizes. </p>
  
  <p>Here is my current result:</p>
  
  <p><img src="https://i.stack.imgur.com/XvKZU.png" width="200"></p>
  
  <p>And here is the code:</p>
  
  <pre><code>struct LandmarkList : View {
      var body: some View {
          NavigationView {
              ScrollView() {
                  VStack {
                      Spacer().frame(height: 160)
                      ForEach(landmarkData) { landmark in
                          LandmarkRow(landmark: landmark).padding([.leading, .trailing], 16)
                      }
                  }.scaledToFill()
                  .background(Color.pink)
              }
              .background(Color.yellow)
              .edgesIgnoringSafeArea(.all)
              .navigationBarTitle(Text("Landmarks"))
  
          }
      }
  }
  
  struct LandmarkRow : View {
      var landmark: Landmark
  
      var body: some View {
          HStack {
              VStack(alignment: .leading) {
                  Text(landmark.name).font(.title)
                  Text("Subtitle")
                      .font(.callout)
                      .color(.gray)
              }
              Spacer()
              Text("5 mi")
                  .font(.largeTitle)
              }.frame(height: 80)
              .padding()
              .background(Color.white)
              .cornerRadius(16)
              .clipped()
              .shadow(radius: 2)
      }
  }
  </code></pre>