Revert of Introduce a type of View background that stays in sync with its host

ash/system/tray/tray_constants.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_constants.h"
 
 #include "base/logging.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/gfx/color_palette.h"
 
@@ skipping 46 matching lines @@
 const int kTrayDetailedViewTransitionDelayMs = 100;
 
 const int kTrayPopupLabelRightPadding = 8;
 
 const int kTrayPopupDetailsIconWidth = 25;
 const SkColor kTrayPopupHoverBackgroundColor = SkColorSetRGB(0xe4, 0xe4, 0xe4);
 const int kTrayRoundedBorderRadius = 2;
 
 const int kTrayToggleButtonWidth = 68;
 
+const SkColor kBackgroundColor = SK_ColorWHITE;
 const SkColor kPublicAccountUserCardTextColor = SkColorSetRGB(0x66, 0x66, 0x66);
 const SkColor kPublicAccountUserCardNameColor = SK_ColorBLACK;
 
 const SkColor kHeaderBackgroundColor = SkColorSetRGB(0xf5, 0xf5, 0xf5);
 
 const SkColor kHeaderTextColorNormal = SkColorSetARGB(0x7f, 0, 0, 0);
 const SkColor kHeaderTextColorHover = SkColorSetARGB(0xd3, 0, 0, 0);
 
 const int kTrayPopupMinWidth = 300;
 const int kTrayPopupMaxWidth = 500;
@@ skipping 22 matching lines @@
 
 const SkColor kTrayPopupInkDropBaseColor = SK_ColorBLACK;
 const float kTrayPopupInkDropRippleOpacity = 0.06f;
 const float kTrayPopupInkDropHighlightOpacity = 0.08f;
 const int kTrayPopupInkDropInset = 4;
 const int kTrayPopupInkDropCornerRadius = 2;
 
 const int kTrayPopupSystemInfoRowHeight = 40;
 
 }  // namespace ash