Update TrayPopupHeaderButton Visual Feedback

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 "ash/ash_switches.h"
 #include "third_party/skia/include/core/SkColor.h"
 
 namespace ash {
@@ skipping 32 matching lines @@
 
 const int kTrayPopupAutoCloseDelayInSeconds = 2;
 const int kTrayPopupAutoCloseDelayForTextInSeconds = 5;
 const int kTrayPopupPaddingHorizontal = 18;
 const int kTrayPopupPaddingBetweenItems = 10;
 const int kTrayPopupTextSpacingVertical = 4;
 const int kTrayPopupUserCardVerticalPadding = 10;
 
 const int kTrayPopupDetailsIconWidth = 25;
 const int kTrayPopupDetailsLabelExtraLeftMargin = 8;
+const SkColor kTrayPopupHoverBackgroundColor = SkColorSetRGB(0xe4, 0xe4, 0xe4);
 const int kTrayPopupScrollSeparatorHeight = 15;
 const int kTrayRoundedBorderRadius = 2;
 const int kTrayBarButtonWidth = 39;
 
 const SkColor kBackgroundColor = SkColorSetRGB(0xfe, 0xfe, 0xfe);
 const SkColor kHoverBackgroundColor = SkColorSetRGB(0xf3, 0xf3, 0xf3);
 const SkColor kPublicAccountBackgroundColor = SkColorSetRGB(0xf8, 0xe5, 0xb6);
 const SkColor kPublicAccountUserCardTextColor = SkColorSetRGB(0x66, 0x66, 0x66);
 const SkColor kPublicAccountUserCardNameColor = SK_ColorBLACK;
 
@@ skipping 14 matching lines @@
     (kNotificationIconWidth + kNotificationButtonWidth +
      (kTrayPopupPaddingHorizontal / 2) * 3);
 
 const int kTrayAvatarCornerRadius = 2;
 const int kTrayAvatarSize = 32;
 
 const int kTraySpacing = 4;
 const int kShelfItemHeight = 38;
 
 }  // namespace ash