Make TestRenderWidgetHostView::Show/Hide call through to RWHI

content/browser/renderer_host/render_widget_host_view_base.cc

Index: content/browser/renderer_host/render_widget_host_view_base.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_base.cc b/content/browser/renderer_host/render_widget_host_view_base.cc
index 780ced5af6016c192761f09227148b61bae5ff28..1fea2843dfe3b14b53c943a9250d8ccf302d2356 100644
--- a/content/browser/renderer_host/render_widget_host_view_base.cc
+++ b/content/browser/renderer_host/render_widget_host_view_base.cc
@@ -401,8 +401,10 @@ bool RenderWidgetHostViewBase::GetBackgroundOpaque() {
 }
 
 gfx::Size RenderWidgetHostViewBase::GetPhysicalBackingSize() const {
-  gfx::Display display =
-      gfx::Screen::GetScreen()->GetDisplayNearestWindow(GetNativeView());
+  gfx::Screen* screen = gfx::Screen::GetScreen();
+  if (!screen)
+    return gfx::Size();
+  gfx::Display display = screen->GetDisplayNearestWindow(GetNativeView());
   return gfx::ScaleToCeiledSize(GetRequestedRendererSize(),
                                 display.device_scale_factor());
 }