Use "static_assert" in lieu of "COMPILE_ASSERT" in ash module

ash/wm/wm_types.cc

Index: ash/wm/wm_types.cc
diff --git a/ash/wm/wm_types.cc b/ash/wm/wm_types.cc
index 6869426c6982670cb9a11cca6147adc9345760cf..643520c36dd0262d04c0094083b5f493359b1999 100644
--- a/ash/wm/wm_types.cc
+++ b/ash/wm/wm_types.cc
@@ -11,10 +11,9 @@ namespace ash {
 namespace wm {
 
 // This is to catch the change to WindowShowState.
-COMPILE_ASSERT(
-    ui::SHOW_STATE_END ==
-    static_cast<ui::WindowShowState>(WINDOW_STATE_TYPE_END),
-    show_enum_mismatch);
+static_assert(ui::SHOW_STATE_END ==
+                  static_cast<ui::WindowShowState>(WINDOW_STATE_TYPE_END),
+              "show enum mismatch");
 
 WindowStateType ToWindowStateType(ui::WindowShowState state) {
   return static_cast<WindowStateType>(state);