Add Flex to views::BoxLayout.

ash/system/tray/tray_background_view.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/system/tray/tray_background_view.h"
 
 #include "ash/ash_switches.h"
 #include "ash/root_window_controller.h"
 #include "ash/screen_util.h"
 #include "ash/shelf/shelf_layout_manager.h"
@@ skipping 258 matching lines @@
   if (alignment_ == SHELF_ALIGNMENT_BOTTOM ||
       alignment_ == SHELF_ALIGNMENT_TOP) {
     SetBorder(views::Border::CreateEmptyBorder(
         kPaddingFromEdgeOfShelf,
         kPaddingFromEdgeOfShelf,
         kPaddingFromEdgeOfShelf,
         kPaddingFromEdgeOfShelf));
 
     views::BoxLayout* layout =
         new views::BoxLayout(views::BoxLayout::kHorizontal, 0, 0, 0);
-    layout->set_main_axis_alignment(views::BoxLayout::MAIN_AXIS_ALIGNMENT_FILL);
+    layout->set_default_flex(1);
     views::View::SetLayoutManager(layout);
   } else {
     SetBorder(views::Border::CreateEmptyBorder(
         kPaddingFromEdgeOfShelf,
         kPaddingFromEdgeOfShelf,
         kPaddingFromEdgeOfShelf,
         kPaddingFromEdgeOfShelf));
 
     views::BoxLayout* layout =
         new views::BoxLayout(views::BoxLayout::kVertical, 0, 0, 0);
-    layout->set_main_axis_alignment(views::BoxLayout::MAIN_AXIS_ALIGNMENT_FILL);
+    layout->set_default_flex(1);
     views::View::SetLayoutManager(layout);
   }
   PreferredSizeChanged();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // TrayBackgroundView
 
 TrayBackgroundView::TrayBackgroundView(StatusAreaWidget* status_area_widget)
     : status_area_widget_(status_area_widget),
@@ skipping 309 matching lines @@
     background_->set_alpha(kTrayBackgroundAlpha);
   SchedulePaint();
 }
 
 void TrayBackgroundView::UpdateBubbleViewArrow(
     views::TrayBubbleView* bubble_view) {
   // Nothing to do here.
 }
 
 }  // namespace ash