ash: Add ShelfObserver::OnShelfWorkAreaInsetsChanged

- Add ShelfLayoutManager::OnWorkAreaInsetsChanged that notifies
  Shelf when it updates the Shelf insets in WorkAreaInsets;
- Add ShelfObserver::OnShelfWorkAreaInsetsChanged that gets called
  when Shelf gets a OnWorkAreaInsetsChanged call;
- AshPopupAlignmentDelegate observes OnShelfWorkAreaInsetsChanged
  and update its work area instead Shelf visibility or autohide
  state change;

Bug: 1002003
Change-Id: I1239713a1d1dd7c27d84cfe4f81621f4ab638ecf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1795907
Commit-Queue: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Manu Cornet <manucornet@chromium.org>
Reviewed-by: Evan Stade <estade@chromium.org>
Cr-Commit-Position: refs/heads/master@{#695332}

ash/shelf/shelf.cc

@@ -391,6 +391,11 @@ void Shelf::OnBackgroundUpdated(ShelfBackgroundType background_type,
     observer.OnBackgroundTypeChanged(background_type, change_type);
 }
 
+void Shelf::OnWorkAreaInsetsChanged() {
+  for (auto& observer : observers_)
+    observer.OnShelfWorkAreaInsetsChanged();
+}
+
 WorkAreaInsets* Shelf::GetWorkAreaInsets() const {
   const aura::Window* window = GetWindow();
   DCHECK(window);

ash/shelf/shelf.h

@@ -189,6 +189,7 @@ class ASH_EXPORT Shelf : public ShelfLayoutManagerObserver {
   void OnAutoHideStateChanged(ShelfAutoHideState new_state) override;
   void OnBackgroundUpdated(ShelfBackgroundType background_type,
                            AnimationChangeType change_type) override;
+  void OnWorkAreaInsetsChanged() override;
 
  private:
   class AutoHideEventHandler;

ash/shelf/shelf_layout_manager.cc

@@ -1452,6 +1452,8 @@ void ShelfLayoutManager::CalculateTargetBoundsAndUpdateWorkArea(
   WorkAreaInsets::ForWindow(shelf_widget_->GetNativeWindow())
       ->SetShelfBoundsAndInsets(target_bounds->shelf_bounds,
                                 target_bounds->shelf_insets);
+  for (auto& observer : observers_)
+    observer.OnWorkAreaInsetsChanged();
 }
 
 void ShelfLayoutManager::UpdateTargetBoundsForGesture(

ash/shelf/shelf_layout_manager_observer.h

@@ -32,6 +32,10 @@ class ASH_EXPORT ShelfLayoutManagerObserver {
 
   // Called when the hotseat state changes.
   virtual void OnHotseatStateChanged(HotseatState state) {}
+
+  // Called when ShelfLayoutManager has updated Shelf insets in work area
+  // insets.
+  virtual void OnWorkAreaInsetsChanged() {}
 };
 
 }  // namespace ash

ash/shelf/shelf_observer.h

@@ -15,12 +15,22 @@ enum class AnimationChangeType;
 // Used to observe changes to the shelf.
 class ASH_EXPORT ShelfObserver {
  public:
+  // Invoked when background type is changed.
   virtual void OnBackgroundTypeChanged(ShelfBackgroundType background_type,
                                        AnimationChangeType change_type) {}
+
+  // Invoked when Shelf's visibility state will be changed to |new_state|.
   virtual void WillChangeVisibilityState(ShelfVisibilityState new_state) {}
+
+  // Invoked when Shelf's auto hide state is changed to |new_state|.
   virtual void OnAutoHideStateChanged(ShelfAutoHideState new_state) {}
+
+  // Invoked when the positions of Shelf Icons are changed.
   virtual void OnShelfIconPositionsChanged() {}
 
+  // Invoked when the Shelf has updated its insets in work area insets.
+  virtual void OnShelfWorkAreaInsetsChanged() {}
+
  protected:
   virtual ~ShelfObserver() {}
 };

ash/system/message_center/ash_popup_alignment_delegate.cc

@@ -147,13 +147,7 @@ void AshPopupAlignmentDelegate::UpdateWorkArea() {
 ///////////////////////////////////////////////////////////////////////////////
 // ShelfObserver:
 
-void AshPopupAlignmentDelegate::WillChangeVisibilityState(
-    ShelfVisibilityState new_state) {
-  UpdateWorkArea();
-}
-
-void AshPopupAlignmentDelegate::OnAutoHideStateChanged(
-    ShelfAutoHideState new_state) {
+void AshPopupAlignmentDelegate::OnShelfWorkAreaInsetsChanged() {
   UpdateWorkArea();
 }
 

ash/system/message_center/ash_popup_alignment_delegate.h

@@ -73,8 +73,7 @@ class ASH_EXPORT AshPopupAlignmentDelegate
   void UpdateWorkArea();
 
   // ShelfObserver:
-  void WillChangeVisibilityState(ShelfVisibilityState new_state) override;
-  void OnAutoHideStateChanged(ShelfAutoHideState new_state) override;
+  void OnShelfWorkAreaInsetsChanged() override;
 
   // Overridden from display::DisplayObserver:
   void OnDisplayMetricsChanged(const display::Display& display,

ash/system/message_center/ash_popup_alignment_delegate_unittest.cc

@@ -18,6 +18,7 @@
 #include "ash/shell.h"
 #include "ash/test/ash_test_base.h"
 #include "ash/wm/desks/desks_util.h"
+#include "ash/wm/overview/overview_controller.h"
 #include "base/command_line.h"
 #include "ui/display/manager/display_manager.h"
 #include "ui/display/screen.h"
@@ -252,4 +253,31 @@ TEST_F(AshPopupAlignmentDelegateTest, KeyboardShowing) {
   EXPECT_EQ(baseline, alignment_delegate()->GetBaseline());
 }
 
+// Tests that notification bubble baseline is correct when entering and exiting
+// overview with a full screen window.
+TEST_F(AshPopupAlignmentDelegateTest, BaselineInOverview) {
+  UpdateDisplay("800x600");
+
+  ASSERT_TRUE(GetPrimaryShelf()->IsHorizontalAlignment());
+  ASSERT_EQ(SHELF_VISIBLE, GetPrimaryShelf()->GetVisibilityState());
+  const int baseline_with_visible_shelf = alignment_delegate()->GetBaseline();
+
+  std::unique_ptr<views::Widget> widget = CreateTestWidget();
+  widget->SetFullscreen(true);
+  ASSERT_EQ(SHELF_HIDDEN, GetPrimaryShelf()->GetVisibilityState());
+  const int baseline_with_hidden_shelf = alignment_delegate()->GetBaseline();
+  EXPECT_NE(baseline_with_visible_shelf, baseline_with_hidden_shelf);
+
+  auto* overview_controller = Shell::Get()->overview_controller();
+  overview_controller->StartOverview();
+  EXPECT_TRUE(overview_controller->InOverviewSession());
+  const int baseline_in_overview = alignment_delegate()->GetBaseline();
+  EXPECT_EQ(baseline_in_overview, baseline_with_visible_shelf);
+
+  overview_controller->EndOverview();
+  EXPECT_FALSE(overview_controller->InOverviewSession());
+  const int baseline_no_overview = alignment_delegate()->GetBaseline();
+  EXPECT_EQ(baseline_no_overview, baseline_with_hidden_shelf);
+}
+
 }  // namespace ash