[MD] Fix clipping of infobar child elements (particularly close button).

chrome/browser/ui/views/infobars/infobar_view.h

Index: chrome/browser/ui/views/infobars/infobar_view.h
diff --git a/chrome/browser/ui/views/infobars/infobar_view.h b/chrome/browser/ui/views/infobars/infobar_view.h
index 919284804a3a0f81e201fc62f8627727d3db02b8..9486766001cd0c1bf628594375076c65f4513cd4 100644
--- a/chrome/browser/ui/views/infobars/infobar_view.h
+++ b/chrome/browser/ui/views/infobars/infobar_view.h
@@ -92,9 +92,9 @@ class InfoBarView : public infobars::InfoBar,
   int StartX() const;
   int EndX() const;
 
-  // Given a |view|, returns the centered y position within us, taking into
-  // account animation so the control "slides in" (or out) as we animate open
-  // and closed.
+  // Given a |view|, returns the centered y position within |child_container_|,
+  // taking into account animation so the control "slides in" (or out) as we
+  // animate open and closed.
   int OffsetY(views::View* view) const;
 
   // Convenience getter.
@@ -107,6 +107,11 @@ class InfoBarView : public infobars::InfoBar,
                  views::MenuButton* button,
                  views::MenuAnchorPosition anchor);
 
+ protected:
+  // Adds |view| to the content area, i.e. |child_container_|. The |view| won't
+  // automatically get any layout, so should still be laid out manually.
+  void AddViewToContentArea(views::View* view);
+
  private:
   // Does the actual work for AssignWidths().  Assumes |labels| is sorted by
   // decreasing preferred width.
@@ -120,11 +125,14 @@ class InfoBarView : public infobars::InfoBar,
   // views::View:
   void GetAccessibleState(ui::AXViewState* state) override;
   gfx::Size GetPreferredSize() const override;
-  void PaintChildren(const ui::PaintContext& context) override;
 
   // views::ExternalFocusTracker:
   void OnWillChangeFocus(View* focused_before, View* focused_now) override;
 
+  // This container holds the children and clips their painting during
+  // animation.
+  views::View* child_container_;
+
   // The optional icon at the left edge of the InfoBar.
   views::ImageView* icon_;