[ash-md] Remove non-md code from the Shelf background animations.

ash/common/shelf/shelf_constants.cc

Index: ash/common/shelf/shelf_constants.cc
diff --git a/ash/common/shelf/shelf_constants.cc b/ash/common/shelf/shelf_constants.cc
index b9a573dc21d6a9e7aaffcd69803c4a90c61f675b..c3377bbd455927cf8615028e60a129f9d2fde097 100644
--- a/ash/common/shelf/shelf_constants.cc
+++ b/ash/common/shelf/shelf_constants.cc
@@ -21,12 +21,12 @@ const SkColor kShelfButtonActivatedHighlightColor =
 const SkColor kShelfInkDropBaseColor = SK_ColorWHITE;
 const float kShelfInkDropVisibleOpacity = 0.2f;
 const SkColor kShelfIconColor = SK_ColorWHITE;
+const int kShelfTranslucentAlpha = 153;
 const int kOverflowButtonSize = 32;
 const int kOverflowButtonCornerRadius = 2;
 const int kAppListButtonRadius = kOverflowButtonSize / 2;
 
 int GetShelfConstant(ShelfConstant shelf_constant) {
-  const int kShelfBackgroundAlpha[] = {204, 153, 153};
   const int kShelfSize[] = {47, 48, 48};
   const int kShelfButtonSpacing[] = {10, 16, 16};
   const int kShelfButtonSize[] = {44, 48, 48};
@@ -37,8 +37,6 @@ int GetShelfConstant(ShelfConstant shelf_constant) {
          mode <= MaterialDesignController::MATERIAL_EXPERIMENTAL);
 
   switch (shelf_constant) {
-    case SHELF_BACKGROUND_ALPHA:
-      return kShelfBackgroundAlpha[mode];
     case SHELF_SIZE:
       return kShelfSize[mode];
     case SHELF_BUTTON_SPACING: