Specify a default display UI scale to reset the zoom to

ash/display/window_tree_host_manager_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/display/window_tree_host_manager.h"
 
 #include <memory>
 
 #include "ash/aura/wm_window_aura.h"
 #include "ash/common/material_design/material_design_controller.h"
@@ skipping 726 matching lines @@
   // Changing internal ID display changes the DisplayIdPair (it comes
   // first), which also changes the primary display candidate.  Update
   // the primary display manually to update the primary display to
   // avoid getting the OnDisplayConfigurationChanged() call twice in
   // SetDisplayUIScale. Note that this scenario will never happen on
   // real devices.
   Shell::GetInstance()->window_tree_host_manager()->SetPrimaryDisplayId(
       secondary_id);
   EXPECT_EQ(1, observer.CountAndReset());
 
-  display_manager()->SetDisplayUIScale(secondary_id, 1.125f);
+  test::DisplayManagerTestApi(display_manager())
+      .SetDisplayUIScale(secondary_id, 1.125f);
   EXPECT_EQ(1, observer.CountAndReset());
   EXPECT_EQ(0, observer.GetFocusChangedCountAndReset());
   EXPECT_EQ(0, observer.GetActivationChangedCountAndReset());
-  display_manager()->SetDisplayUIScale(secondary_id, 1.125f);
+  test::DisplayManagerTestApi(display_manager())
+      .SetDisplayUIScale(secondary_id, 1.125f);
   EXPECT_EQ(0, observer.CountAndReset());
   EXPECT_EQ(0, observer.GetFocusChangedCountAndReset());
   EXPECT_EQ(0, observer.GetActivationChangedCountAndReset());
-  display_manager()->SetDisplayUIScale(primary_id, 1.125f);
+  test::DisplayManagerTestApi(display_manager())
+      .SetDisplayUIScale(primary_id, 1.125f);
   EXPECT_EQ(0, observer.CountAndReset());
   EXPECT_EQ(0, observer.GetFocusChangedCountAndReset());
   EXPECT_EQ(0, observer.GetActivationChangedCountAndReset());
-  display_manager()->SetDisplayUIScale(primary_id, 1.125f);
+  test::DisplayManagerTestApi(display_manager())
+      .SetDisplayUIScale(primary_id, 1.125f);
   EXPECT_EQ(0, observer.CountAndReset());
   EXPECT_EQ(0, observer.GetFocusChangedCountAndReset());
   EXPECT_EQ(0, observer.GetActivationChangedCountAndReset());
 }
 
 TEST_P(WindowTreeHostManagerTest, FindNearestDisplay) {
   if (!SupportsMultipleDisplays())
     return;
 
   WindowTreeHostManager* window_tree_host_manager =
@@ skipping 366 matching lines @@
   EXPECT_EQ("0,0 450x300", display1.bounds().ToString());
   EXPECT_EQ("0,0 450x300", root_windows[0]->bounds().ToString());
   EXPECT_EQ("450,0 500x300", display2.bounds().ToString());
   EXPECT_EQ(1.5f, GetStoredUIScale(display1.id()));
   EXPECT_EQ(1.0f, GetStoredUIScale(display2.id()));
 
   ui::test::EventGenerator generator(root_windows[0]);
   generator.MoveMouseToInHost(599, 200);
   EXPECT_EQ("449,150", event_handler.GetLocationAndReset());
 
-  display_manager()->SetDisplayUIScale(display1.id(), 1.25f);
+  test::DisplayManagerTestApi(display_manager())
+      .SetDisplayUIScale(display1.id(), 1.25f);
   display1 = display::Screen::GetScreen()->GetPrimaryDisplay();
   display2 = display_manager()->GetSecondaryDisplay();
   EXPECT_EQ("0,0 375x250", display1.bounds().ToString());
   EXPECT_EQ("0,0 375x250", root_windows[0]->bounds().ToString());
   EXPECT_EQ("375,0 500x300", display2.bounds().ToString());
   EXPECT_EQ(1.25f, GetStoredUIScale(display1.id()));
   EXPECT_EQ(1.0f, GetStoredUIScale(display2.id()));
 
   Shell::GetInstance()->RemovePreTargetHandler(&event_handler);
 }
@@ skipping 404 matching lines @@
       widget->GetNativeWindow()->GetRootWindow());
   event_generator.MoveMouseToCenterOf(widget->GetNativeWindow());
 
   UpdateDisplay("300x300");
   watcher.Stop();
 
   widget->CloseNow();
 }
 
 }  // namespace ash