Refactor screen/monitor so that gfx::Screen returns monitor object.

ui/gfx/screen_android.cc

Index: ui/gfx/screen_android.cc
diff --git a/ui/gfx/screen_android.cc b/ui/gfx/screen_android.cc
index 27a60c16a7229a9a0b5bba881de28d4c9c5b2a8b..037329c17c03e2ed7cebbd450c151b1fa5a50683 100644
--- a/ui/gfx/screen_android.cc
+++ b/ui/gfx/screen_android.cc
@@ -5,13 +5,15 @@
 #include "ui/gfx/screen.h"
 
 #include "base/logging.h"
+#include "ui/gfx/monitor.h"
 
 namespace gfx {
 
 // static
-gfx::Size Screen::GetPrimaryMonitorSize() {
+const gfx::Monitor* Screen::GetPrimaryMonitor() {
+  static SimpleMonitor* monitor = new SimpleMonitor();
   NOTIMPLEMENTED() << "crbug.com/117839 tracks implementation";
-  return gfx::Size(1, 1);
+  return monitor;
 }
 
 // static