ash: Show better focus rects for the tray.

ash/system/tray/tray_views.h

Index: ash/system/tray/tray_views.h
diff --git a/ash/system/tray/tray_views.h b/ash/system/tray/tray_views.h
index e06c57418ab4024a70fac088d0829999a0b81e67..f1c99a1f0bb8407000ab8148d80ca5c8fd6d80a2 100644
--- a/ash/system/tray/tray_views.h
+++ b/ash/system/tray/tray_views.h
@@ -10,6 +10,7 @@
 #include "ui/gfx/size.h"
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/scroll_view.h"
+#include "ui/views/controls/slider.h"
 #include "ui/views/view.h"
 
 class SkBitmap;
@@ -55,6 +56,7 @@ class ActionableView : public views::View {
   // Overridden from views::View.
   virtual bool OnKeyPressed(const views::KeyEvent& event) OVERRIDE;
   virtual bool OnMousePressed(const views::MouseEvent& event) OVERRIDE;
+  virtual void OnPaintFocusBorder(gfx::Canvas* canvas) OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ActionableView);
@@ -130,6 +132,19 @@ class FixedSizedScrollView : public views::ScrollView {
   DISALLOW_COPY_AND_ASSIGN(FixedSizedScrollView);
 };
 
+// A slider with a custom focus border (with greater accessibility).
+class AccessibleSlider : public views::Slider {
+ public:
+  AccessibleSlider(views::SliderListener* listener, Orientation orientation);
+  virtual ~AccessibleSlider();
+
+ private:
+  // Overridden from views::View.
+  void OnPaintFocusBorder(gfx::Canvas* canvas) OVERRIDE;
+
+  DISALLOW_COPY_AND_ASSIGN(AccessibleSlider);
+};
+
 // Creates a container for the various detailed popups. Clicking on the view
 // triggers the callback in ViewClickListener.
 views::View* CreateDetailedHeaderEntry(int string_id,