view-mus: Fix DisableViewDoesNotActivateWidget by adding Show().

NWA was allowing invisible widgets to be activated, which
doesn't work in mus.

BUG=678070

Review-Url: https://codereview.chromium.org/2615743003
Cr-Commit-Position: refs/heads/master@{#442705}

ui/views/widget/widget_interactive_uitest.cc

@@ -998,10 +998,6 @@ TEST_F(WidgetTestInteractive, TouchSelectionQuickMenuIsNotActivated) {
 #endif  // defined(USE_AURA)
 
 TEST_F(WidgetTestInteractive, DisableViewDoesNotActivateWidget) {
-  // TODO: see http://crbug.com/678070 for details.
-  if (IsMus())
-    return;
-
 #if defined(OS_WIN)
   views_delegate()->set_use_desktop_native_widgets(true);
 #endif  // !defined(OS_WIN)
@@ -1017,6 +1013,7 @@ TEST_F(WidgetTestInteractive, DisableViewDoesNotActivateWidget) {
   view1->SetFocusBehavior(View::FocusBehavior::ALWAYS);
   widget1.GetRootView()->AddChildView(view1);
 
+  widget1.Show();
   ActivateSync(&widget1);
 
   FocusManager* focus_manager1 = widget1.GetFocusManager();
@@ -1035,6 +1032,7 @@ TEST_F(WidgetTestInteractive, DisableViewDoesNotActivateWidget) {
   view2->SetFocusBehavior(View::FocusBehavior::ALWAYS);
   widget2.GetRootView()->AddChildView(view2);
 
+  widget2.Show();
   ActivateSync(&widget2);
   EXPECT_TRUE(widget2.IsActive());
   EXPECT_FALSE(widget1.IsActive());