Make spacing between uber tray items consistent with UI spec.

ash/system/tray/system_tray_item.cc

Index: ash/system/tray/system_tray_item.cc
diff --git a/ash/system/tray/system_tray_item.cc b/ash/system/tray/system_tray_item.cc
index 7c7fec84258f39f7fabd595529be643330d08acb..0543751e04b46c19e5d91161aba09f48033c1bbd 100644
--- a/ash/system/tray/system_tray_item.cc
+++ b/ash/system/tray/system_tray_item.cc
@@ -6,6 +6,9 @@
 
 #include "ash/shell.h"
 #include "ash/system/tray/system_tray.h"
+#include "ash/system/tray/tray_constants.h"
+#include "ash/system/tray/tray_item_view.h"
+#include "ui/views/controls/label.h"
 #include "ui/views/view.h"
 
 namespace ash {
@@ -60,6 +63,39 @@ void SystemTrayItem::PopupDetailedView(int for_seconds, bool activate) {
       this, for_seconds, activate, BUBBLE_CREATE_NEW);
 }
 
+void SystemTrayItem::SetTrayImageItemBorder(views::View* tray_view,
+                                            ShelfAlignment alignment) {
+  if (alignment == SHELF_ALIGNMENT_BOTTOM) {
+    tray_view->set_border(views::Border::CreateEmptyBorder(
+        0, kTrayImageItemHorizontalPaddingBottomAlignment,
+        0, kTrayImageItemHorizontalPaddingBottomAlignment));
+  } else {
+    tray_view->set_border(views::Border::CreateEmptyBorder(
+        kTrayImageItemVerticalPaddingVerticalAlignment,
+        kTrayImageItemHorizontalPaddingVerticalAlignment,
+        kTrayImageItemVerticalPaddingVerticalAlignment,
+        kTrayImageItemHorizontalPaddingVerticalAlignment));
+  }
+}
+
+void SystemTrayItem::SetTrayLabelItemBorder(internal::TrayItemView* tray_view,
+                                            ShelfAlignment alignment) {
+  if (alignment == SHELF_ALIGNMENT_BOTTOM) {
+    tray_view->set_border(views::Border::CreateEmptyBorder(
+        0, kTrayLabelItemHorizontalPaddingBottomAlignment,
+        0, kTrayLabelItemHorizontalPaddingBottomAlignment));
+  } else {
+    // Center the label for vertical launcher alignment.
+    int horizontal_padding = (tray_view->GetPreferredSize().width() -
+        tray_view->label()->GetPreferredSize().width()) / 2;
+    tray_view->set_border(views::Border::CreateEmptyBorder(
+        kTrayLabelItemVerticalPaddingVeriticalAlignment,
+        horizontal_padding,
+        kTrayLabelItemVerticalPaddingVeriticalAlignment,
+        horizontal_padding));
+  }
+}
+
 void SystemTrayItem::SetDetailedViewCloseDelay(int for_seconds) {
   Shell::GetInstance()->system_tray()->SetDetailedViewCloseDelay(for_seconds);
 }