Adjust bubble size in response to screen configuration change.

As a known issue, this doesn't respond to turning on/off the docked
magnifier.

Test: manually verified by rotating screen and zooming by ctrl-shift-+.
Bug: 862575
Change-Id: I7e74b4ce701c017b77df59cce00a30b0c3ebc821
Reviewed-on: https://chromium-review.googlesource.com/1134633Reviewed-by: Yoshiki Iguchi <yoshiki@chromium.org>
Commit-Queue: Tatsuhisa Yamaguchi <yamaguchi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#575944}

ash/system/unified/unified_system_tray_bubble.cc

@@ -81,17 +81,10 @@ UnifiedSystemTrayBubble::UnifiedSystemTrayBubble(UnifiedSystemTray* tray,
 
   bubble_view_ = new views::TrayBubbleView(init_params);
 
-  // TODO(yamaguchi): Reconsider this formula. The y-position of the top edge
-  // still differes by few pixels between the horizontal and vertical shelf
-  // modes.
-  int free_space_height_above_anchor =
-      tray->shelf()->GetSystemTrayAnchor()->GetBoundsInScreen().y() -
-      tray->shelf()->GetUserWorkAreaBounds().y();
-  int max_height = free_space_height_above_anchor - kPaddingFromScreenTop -
-                   bubble_view_->GetBorderInsets().height();
   unified_view_ = controller_->CreateView();
   time_to_click_recorder_ =
       std::make_unique<TimeToClickRecorder>(this, unified_view_);
+  int max_height = CalculateMaxHeight();
   unified_view_->SetMaxHeight(max_height);
   bubble_view_->SetMaxHeight(max_height);
   bubble_view_->AddChildView(new ContainerView(unified_view_));
@@ -214,6 +207,21 @@ views::Widget* UnifiedSystemTrayBubble::GetBubbleWidget() const {
   return bubble_widget_;
 }
 
+int UnifiedSystemTrayBubble::CalculateMaxHeight() const {
+  // TODO(yamaguchi): Reconsider this formula. The y-position of the top edge
+  // still differes by few pixels between the horizontal and vertical shelf
+  // modes.
+  int free_space_height_above_anchor =
+      tray_->shelf()->GetSystemTrayAnchor()->GetBoundsInScreen().y() -
+      tray_->shelf()->GetUserWorkAreaBounds().y();
+  return free_space_height_above_anchor - kPaddingFromScreenTop -
+         bubble_view_->GetBorderInsets().height();
+}
+
+void UnifiedSystemTrayBubble::OnDisplayConfigurationChanged() {
+  UpdateBubbleBounds();
+}
+
 void UnifiedSystemTrayBubble::OnWidgetDestroying(views::Widget* widget) {
   CHECK_EQ(bubble_widget_, widget);
   bubble_widget_->RemoveObserver(this);
@@ -241,6 +249,9 @@ void UnifiedSystemTrayBubble::OnTabletModeEnded() {
 }
 
 void UnifiedSystemTrayBubble::UpdateBubbleBounds() {
+  int max_height = CalculateMaxHeight();
+  unified_view_->SetMaxHeight(max_height);
+  bubble_view_->SetMaxHeight(max_height);
   // If the bubble is open while switching to and from tablet mode, change the
   // bubble anchor if needed. The new anchor view may also have a translation
   // applied to it so shift the bubble bounds so that it appears in the correct

ash/system/unified/unified_system_tray_bubble.h

@@ -7,6 +7,7 @@
 
 #include <memory>
 
+#include "ash/system/screen_layout_observer.h"
 #include "ash/system/tray/time_to_click_recorder.h"
 #include "ash/system/tray/tray_bubble_base.h"
 #include "ash/wm/tablet_mode/tablet_mode_observer.h"
@@ -35,6 +36,7 @@ class UnifiedSystemTrayView;
 // case, this class calls UnifiedSystemTray::CloseBubble() to delete itself.
 class UnifiedSystemTrayBubble : public TrayBubbleBase,
                                 public views::WidgetObserver,
+                                public ash::ScreenLayoutObserver,
                                 public TimeToClickRecorder::Delegate,
                                 public TabletModeObserver {
  public:
@@ -67,6 +69,9 @@ class UnifiedSystemTrayBubble : public TrayBubbleBase,
   views::TrayBubbleView* GetBubbleView() const override;
   views::Widget* GetBubbleWidget() const override;
 
+  // ash::ScreenLayoutObserver:
+  void OnDisplayConfigurationChanged() override;
+
   // views::WidgetObserver:
   void OnWidgetDestroying(views::Widget* widget) override;
 
@@ -117,6 +122,9 @@ class UnifiedSystemTrayBubble : public TrayBubbleBase,
   views::TrayBubbleView* bubble_view_ = nullptr;
   UnifiedSystemTrayView* unified_view_ = nullptr;
 
+ private:
+  int CalculateMaxHeight() const;
+
   DISALLOW_COPY_AND_ASSIGN(UnifiedSystemTrayBubble);
 };