Fix VirtualKeyboardTray border

ash/common/system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc

Index: ash/common/system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc
diff --git a/ash/common/system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc b/ash/common/system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc
index 39eae983dde818d98b91a90c9c0b57ac2322b111..19a6c66273b60c02961b78df9fbd2443ffe56e60 100644
--- a/ash/common/system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc
+++ b/ash/common/system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc
@@ -98,6 +98,8 @@ void VirtualKeyboardTray::OnKeyboardBoundsChanging(
 }
 
 void VirtualKeyboardTray::SetIconBorderForShelfAlignment() {
+  tray_container()->SetBorder(views::Border::NullBorder());

[James Cook, 2016/08/09 15:54:32]

Why does this have to be done every time the shelf alignment changes? If it
can't just be done once, can you add a comment here explaining why it has to be
done each time?

[mohsen, 2016/08/09 16:32:51]

After each shelf alignment change, the border is reset (see
StatusAreaWidgetDelegate::SetBorderOnChild()). Added a comment.

+
   const gfx::ImageSkia& image = icon_->GetImage();
   const int size = GetTrayConstant(VIRTUAL_KEYBOARD_BUTTON_SIZE);
   const int vertical_padding = (size - image.height()) / 2;