ASH: Use virtual screen coordinates in Display::bounds()

ash/monitor/multi_monitor_manager.cc

Index: ash/monitor/multi_monitor_manager.cc
diff --git a/ash/monitor/multi_monitor_manager.cc b/ash/monitor/multi_monitor_manager.cc
index 70bf90de67c3386ded202f8b4a3beec4201d5cda..4591544fe01d839ad096bf463c2d7016f6709db7 100644
--- a/ash/monitor/multi_monitor_manager.cc
+++ b/ash/monitor/multi_monitor_manager.cc
@@ -124,8 +124,8 @@ RootWindow* MultiMonitorManager::CreateRootWindowForMonitor(
   return root_window;
 }
 
-const gfx::Display& MultiMonitorManager::GetDisplayAt(size_t index) {
-  return index < displays_.size() ? displays_[index] : GetInvalidDisplay();
+gfx::Display* MultiMonitorManager::GetDisplayAt(size_t index) {
+  return index < displays_.size() ? &displays_[index] : NULL;
 }
 
 size_t MultiMonitorManager::GetNumDisplays() const {
@@ -136,7 +136,7 @@ const gfx::Display& MultiMonitorManager::GetDisplayNearestWindow(
     const Window* window) const {
   if (!window) {
     MultiMonitorManager* manager = const_cast<MultiMonitorManager*>(this);
-    return manager->GetDisplayAt(0);
+    return *manager->GetDisplayAt(0);
   }
   const RootWindow* root = window->GetRootWindow();
   MultiMonitorManager* manager = const_cast<MultiMonitorManager*>(this);
@@ -148,7 +148,7 @@ const gfx::Display& MultiMonitorManager::GetDisplayNearestPoint(
   // TODO(oshima): For m19, mouse is constrained within
   // the primary window.
   MultiMonitorManager* manager = const_cast<MultiMonitorManager*>(this);
-  return manager->GetDisplayAt(0);
+  return *manager->GetDisplayAt(0);
 }
 
 void MultiMonitorManager::OnRootWindowResized(const aura::RootWindow* root,