Remove unused variables, ash/ edition.

ash/system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc

Index: ash/system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc
diff --git a/ash/system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc b/ash/system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc
index 9de64ed6e7ac3bcae5edbfd8cbdd69510874b313..3258856d2d095a6fb7207046223ef47461f08c9c 100644
--- a/ash/system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc
+++ b/ash/system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc
@@ -73,7 +73,6 @@ void VirtualKeyboardTray::SetShelfAlignment(ShelfAlignment alignment) {
   // vertically aligned as the button would violate the width constraint on the
   // shelf.
   if (IsHorizontalAlignment(alignment)) {
-    gfx::Insets insets = button_->GetInsets();
     int additional_padding = std::max(0, top_padding - left_padding);
     left_padding += additional_padding;
     right_padding += additional_padding;