[ash-md] Fades overview header in and out

ash/common/wm/overview/window_selector_item.h

Index: ash/common/wm/overview/window_selector_item.h
diff --git a/ash/common/wm/overview/window_selector_item.h b/ash/common/wm/overview/window_selector_item.h
index d3467685e639fd637ca260f2d90830debf0eee42..8b445c6e5cb50103c960c8403b92045171dc0ca6 100644
--- a/ash/common/wm/overview/window_selector_item.h
+++ b/ash/common/wm/overview/window_selector_item.h
@@ -113,6 +113,11 @@ class ASH_EXPORT WindowSelectorItem : public views::ButtonListener,
   // Closes |transform_window_|.
   void CloseWindow();
 
+  // Hides the original window header and sets shape or mask on a window.
+  // When masks are used, rounded corner |radius| can be specified.
+  // TODO(varkha): remove |radius|.
+  void HideHeaderAndSetShape(int radius);
+
   // Sets if the item is dimmed in the overview. Changing the value will also
   // change the visibility of the transform windows.
   void SetDimmed(bool dimmed);
@@ -131,6 +136,7 @@ class ASH_EXPORT WindowSelectorItem : public views::ButtonListener,
 
  private:
   class CaptionContainerView;
+  class RoundedContainerView;
   friend class WindowSelectorTest;
 
   // Sets the bounds of this selector's items to |target_bounds| in
@@ -161,6 +167,9 @@ class ASH_EXPORT WindowSelectorItem : public views::ButtonListener,
   // Updates the close buttons accessibility name.
   void UpdateCloseButtonAccessibilityName();
 
+  // Fades out a window caption when exiting overview mode.
+  void FadeOut(std::unique_ptr<views::Widget> widget);
+
   static bool hide_header() { return use_mask_ || use_shape_; }
 
   // True if the item is being shown in the overview, false if it's being
@@ -181,6 +190,14 @@ class ASH_EXPORT WindowSelectorItem : public views::ButtonListener,
   // a window layer for display on another monitor.
   bool in_bounds_update_;
 
+  // True when |this| item is visually selected. Item header is made transparent
+  // when the item is selected.
+  bool selected_;
+
+  // True initially until the UpdateHeaderLayout is invoked for the first time.

[bruthig, 2016/09/02 16:00:13]

This seems inconsistent with where |first_time_update_| is set to true. i.e. in
WindowSelectorItem::CreateWindowLabel().  I would have expected it to be set at
the bottom of WindowSelectorItem::UpdateHeaderLayout().

[varkha, 2016/09/02 21:38:37]

I have removed this in favor for passing the stage (enter / update / exit) into
UpdateHeaderLayout.

+  // Provided in order to set the initial bounds for the header to animate from.
+  bool first_time_update_;
+
   // Label displaying its name (active tab for tabbed windows).
   // With Material Design this Widget owns |caption_container_view_| and is
   // shown above the |transform_window_|.
@@ -190,9 +207,6 @@ class ASH_EXPORT WindowSelectorItem : public views::ButtonListener,
   // Shadow around the item in overview.
   std::unique_ptr<::wm::Shadow> shadow_;
 
-  // Label background widget used to fade in opacity when moving selection.
-  std::unique_ptr<views::Widget> window_label_selector_;
-
   // Container view that owns |window_label_button_view_| and |close_button_|.
   // Only used with Material Design.
   CaptionContainerView* caption_container_view_;
@@ -212,6 +226,10 @@ class ASH_EXPORT WindowSelectorItem : public views::ButtonListener,
   // Guaranteed to be non-null for the lifetime of |this|.
   WindowSelector* window_selector_;
 
+  // Pointer to a view that covers the original header and has rounded top
+  // corners. This view can have its color and opacity animated.
+  RoundedContainerView* background_view_;
+
   // If true, mask the original window header while in overview and make corners
   // rounded using a mask layer. This has performance implications so it can be
   // disabled when there are many windows.