Switch primary display

ash/test/ash_test_base.cc

Index: ash/test/ash_test_base.cc
diff --git a/ash/test/ash_test_base.cc b/ash/test/ash_test_base.cc
index 80c92a6f5fff20fbbf4d0880888529ebdc189082..1676d36733019f1f4b292e5d2a6378442f035d74 100644
--- a/ash/test/ash_test_base.cc
+++ b/ash/test/ash_test_base.cc
@@ -8,6 +8,7 @@
 #include <vector>
 
 #include "ash/display/display_controller.h"
+#include "ash/display/multi_display_manager.h"
 #include "ash/shell.h"
 #include "ash/test/test_shell_delegate.h"
 #include "base/run_loop.h"
@@ -58,7 +59,10 @@ void AshTestBase::SetUp() {
   TestShellDelegate* delegate = new TestShellDelegate;
   ash::Shell::CreateInstance(delegate);
   Shell::GetPrimaryRootWindow()->Show();
-  Shell::GetPrimaryRootWindow()->SetHostSize(gfx::Size(800, 600));
+  // Move the mouse cursor to far away so that native events doesn't
+  // interfere test expectations.
+  Shell::GetPrimaryRootWindow()->MoveCursorTo(gfx::Point(-1000, -1000));
+  UpdateDisplay("800x600");
   Shell::GetInstance()->cursor_manager()->ShowCursor(true);
 
   // Disable animations during tests.
@@ -87,8 +91,11 @@ void AshTestBase::ChangeDisplayConfig(float scale,
 
 void AshTestBase::UpdateDisplay(const std::string& display_specs) {
   std::vector<gfx::Display> displays = CreateDisplaysFromString(display_specs);
-  aura::Env::GetInstance()->display_manager()->
-      OnNativeDisplaysChanged(displays);
+  internal::MultiDisplayManager* display_manager =
+      static_cast<internal::MultiDisplayManager*>(
+          aura::Env::GetInstance()->display_manager());
+  display_manager->SetDisplayIdsForTest(&displays);
+  display_manager->OnNativeDisplaysChanged(displays);
 
   // On non-testing environment, when a secondary display is connected, a new
   // native (i.e. X) window for the display is always created below the previous