Revert of Android: support multiple displays on C++ side

content/public/test/test_renderer_host.h

Index: content/public/test/test_renderer_host.h
diff --git a/content/public/test/test_renderer_host.h b/content/public/test/test_renderer_host.h
index b9d04a20acb5d58023e334b005d496ceeececd9f..afd42d1758b259580651140b016bf8bca7736f86 100644
--- a/content/public/test/test_renderer_host.h
+++ b/content/public/test/test_renderer_host.h
@@ -26,10 +26,6 @@
 namespace test {
 class AuraTestHelper;
 }
-}
-
-namespace display {
-class Screen;
 }
 
 namespace ui {
@@ -282,7 +278,6 @@
 #endif
 #if defined(OS_ANDROID)
   std::unique_ptr<MockGpuChannelEstablishFactory> gpu_channel_factory_;
-  std::unique_ptr<display::Screen> screen_;
 #endif
   RenderViewHostTestEnabler rvh_test_enabler_;