Eliminate ash::internal namespace

ash/system/tray/fixed_sized_image_view.cc

Index: ash/system/tray/fixed_sized_image_view.cc
diff --git a/ash/system/tray/fixed_sized_image_view.cc b/ash/system/tray/fixed_sized_image_view.cc
index d0d49b92f21e2b3589045c7b0f55eb37b7be8447..9eb949723f35b4fcec0c4cff560deda09d4db30b 100644
--- a/ash/system/tray/fixed_sized_image_view.cc
+++ b/ash/system/tray/fixed_sized_image_view.cc
@@ -5,7 +5,6 @@
 #include "ash/system/tray/fixed_sized_image_view.h"
 
 namespace ash {
-namespace internal {
 
 FixedSizedImageView::FixedSizedImageView(int width, int height)
     : width_(width),
@@ -23,5 +22,4 @@ gfx::Size FixedSizedImageView::GetPreferredSize() {
                    height_ ? height_ : size.height());
 }
 
-}  // namespace internal
 }  // namespace ash