Virtual Desks: Unminimize a minimized window when dragged to another desk

Per PM/UX request, when a minimized window is dragged to another desk,
it should show up in the mini_view, and should be unminimized in the
target desk after it has been move to it. Otherwise, the experience
will be confusing since it will just disappear once dropped.

Demo: https://bugs.chromium.org/p/chromium/issues/detail?id=971417#c2

BUG=971417
TEST=Manually, added test.

Change-Id: I9da54f39cad662080a54c4e234254fb7ef651c29
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1647187
Commit-Queue: Ahmed Fakhry <afakhry@chromium.org>
Reviewed-by: Sammie Quon <sammiequon@chromium.org>
Cr-Commit-Position: refs/heads/master@{#666547}

ash/wm/desks/desk.cc

@@ -245,6 +245,12 @@ void Desk::MoveWindowToDesk(aura::Window* window, Desk* target_desk) {
     MoveWindowToDeskInternal(window, target_desk);
 
     windows_.erase(window);
+
+    // Unminimize the window so that it shows up in the mini_view after it had
+    // been dragged and moved to another desk.
+    auto* window_state = wm::GetWindowState(window);
+    if (window_state->IsMinimized())
+      window_state->Unminimize();
   }
 
   NotifyContentChanged();

ash/wm/desks/desks_controller.h

@@ -93,7 +93,8 @@ class ASH_EXPORT DesksController
   void ActivateDesk(const Desk* desk);
 
   // Moves |window| (which must belong to the currently active desk) to
-  // |target_desk| (which must be a different desk).
+  // |target_desk| (which must be a different desk). If |window| is minimized,
+  // it will be unminimized after it's moved to |target_desk|.
   void MoveWindowFromActiveDeskTo(aura::Window* window, Desk* target_desk);
 
   // Called explicitly by the RootWindowController when a root window has been

ash/wm/desks/desks_unittests.cc

@@ -936,6 +936,57 @@ TEST_F(DesksTest, DragWindowToDesk) {
   EXPECT_TRUE(shadow->layer()->GetTargetVisibility());
 }
 
+TEST_F(DesksTest, DragMinimizedWindowToDesk) {
+  auto* controller = DesksController::Get();
+  controller->NewDesk();
+  ASSERT_EQ(2u, controller->desks().size());
+  const Desk* desk_2 = controller->desks()[1].get();
+
+  auto window = CreateTestWindow(gfx::Rect(0, 0, 250, 100));
+  wm::ActivateWindow(window.get());
+  EXPECT_EQ(window.get(), wm::GetActiveWindow());
+
+  // Minimize the window before entering Overview Mode.
+  auto* window_state = wm::GetWindowState(window.get());
+  window_state->Minimize();
+  ASSERT_TRUE(window_state->IsMinimized());
+
+  auto* overview_controller = Shell::Get()->overview_controller();
+  overview_controller->ToggleOverview();
+  EXPECT_TRUE(overview_controller->InOverviewSession());
+  auto* overview_grid = GetOverviewGridForRoot(Shell::GetPrimaryRootWindow());
+  auto* overview_session = overview_controller->overview_session();
+  auto* overview_item =
+      overview_session->GetOverviewItemForWindow(window.get());
+  ASSERT_TRUE(overview_item);
+  const auto* desks_bar_view = overview_grid->GetDesksBarViewForTesting();
+  ASSERT_TRUE(desks_bar_view);
+  ASSERT_EQ(2u, desks_bar_view->mini_views().size());
+
+  // Drag the window to desk_2's mini_view and activate desk_2. Expect that the
+  // window will be in an unminimized state and all its visibility and layer
+  // opacity attributes are correct.
+  auto* desk_2_mini_view = desks_bar_view->mini_views()[1].get();
+  EXPECT_EQ(desk_2, desk_2_mini_view->desk());
+  DragItemToPoint(overview_item,
+                  desk_2_mini_view->GetBoundsInScreen().CenterPoint(),
+                  GetEventGenerator());
+  EXPECT_TRUE(overview_controller->InOverviewSession());
+  EXPECT_TRUE(overview_grid->empty());
+  EXPECT_TRUE(desk_2->windows().contains(window.get()));
+  EXPECT_FALSE(overview_grid->drop_target_widget());
+  DeskSwitchAnimationWaiter waiter;
+  ClickOnMiniView(desk_2_mini_view, GetEventGenerator());
+  waiter.Wait();
+  EXPECT_FALSE(overview_controller->InOverviewSession());
+  EXPECT_TRUE(desk_2->is_active());
+
+  EXPECT_FALSE(window_state->IsMinimized());
+  EXPECT_TRUE(window->IsVisible());
+  EXPECT_TRUE(window->layer()->GetTargetVisibility());
+  EXPECT_EQ(1.f, window->layer()->GetTargetOpacity());
+}
+
 TEST_F(DesksTest, DragWindowToNonMiniViewPoints) {
   auto* controller = DesksController::Get();
   controller->NewDesk();

ash/wm/overview/overview_item.cc

@@ -534,7 +534,7 @@ void OverviewItem::CloseWindow() {
 void OverviewItem::OnMinimizedStateChanged() {
   const bool minimized = transform_window_.IsMinimized();
   caption_container_view_->SetShowPreview(minimized);
-  if (minimized)
+  if (!minimized)
     EnsureVisible();
 
   if (window_surface_cache_observers_) {