Paint tab-loading throbbers into a ui::Layer.

chrome/browser/ui/views/tabs/tab.h

Index: chrome/browser/ui/views/tabs/tab.h
diff --git a/chrome/browser/ui/views/tabs/tab.h b/chrome/browser/ui/views/tabs/tab.h
index 45dcae6ad61de1c593402c65b8468375f1a584bd..039edefc4c35edb871e3d2d184966674bfeb8d8e 100644
--- a/chrome/browser/ui/views/tabs/tab.h
+++ b/chrome/browser/ui/views/tabs/tab.h
@@ -246,8 +246,7 @@ class Tab : public gfx::AnimationDelegate,
   void PaintIcon(gfx::Canvas* canvas);
 
   // Invoked if data_.network_state changes, or the network_state is not none.
-  void AdvanceLoadingAnimation(TabRendererData::NetworkState old_state,
-                               TabRendererData::NetworkState state);
+  void AdvanceLoadingAnimation(TabRendererData::NetworkState state);
 
   // Returns the number of favicon-size elements that can fit in the tab's
   // current size.
@@ -341,15 +340,6 @@ class Tab : public gfx::AnimationDelegate,
   // crashes.
   int favicon_hiding_offset_;
 
-  // The point in time when the tab icon was first painted in the waiting state.
-  base::TimeTicks waiting_start_time_;
-
-  // The point in time when the tab icon was first painted in the loading state.
-  base::TimeTicks loading_start_time_;
-
-  // Paint state for the throbber after the most recent waiting paint.
-  gfx::ThrobberWaitingState waiting_state_;
-
   // Step in the immersive loading progress indicator.
   int immersive_loading_step_;
 
@@ -365,6 +355,7 @@ class Tab : public gfx::AnimationDelegate,
 
   scoped_refptr<gfx::AnimationContainer> animation_container_;
 
+  views::View* throbber_;

[danakj, 2015/10/08 14:09:01]

can this be a scoped_ptr?

[sky, 2015/10/08 15:52:23]

Generally we don't do that as views are implicitly owned by their parent. See
the next three members as examples of what I mean.

   MediaIndicatorButton* media_indicator_button_;
   views::ImageButton* close_button_;
   views::Label* title_;