Refactors WindowResizers to use ash/wm/common

ash/system/overview/overview_button_tray.cc

Index: ash/system/overview/overview_button_tray.cc
diff --git a/ash/system/overview/overview_button_tray.cc b/ash/system/overview/overview_button_tray.cc
index 8a77d6885ac8334c0847c3e90881555fb965ab86..4b152b3be601271554d1897d874d83b6f65d3768 100644
--- a/ash/system/overview/overview_button_tray.cc
+++ b/ash/system/overview/overview_button_tray.cc
@@ -10,6 +10,7 @@
 #include "ash/shell.h"
 #include "ash/system/tray/system_tray_delegate.h"
 #include "ash/system/tray/tray_utils.h"
+#include "ash/wm/common/shelf/wm_shelf_util.h"
 #include "ash/wm/maximize_mode/maximize_mode_controller.h"
 #include "ash/wm/overview/window_selector_controller.h"
 #include "grit/ash_resources.h"
@@ -104,7 +105,7 @@ void OverviewButtonTray::SetShelfAlignment(wm::ShelfAlignment alignment) {
 }
 
 void OverviewButtonTray::SetIconBorderForShelfAlignment() {
-  if (IsHorizontalAlignment(shelf_alignment())) {
+  if (wm::IsHorizontalAlignment(shelf_alignment())) {
     icon_->SetBorder(views::Border::CreateEmptyBorder(
         kHorizontalShelfVerticalPadding,
         kHorizontalShelfHorizontalPadding,