[Code] Make union usage more consistent

src/xenia/kernel/util/xex2_info.h

@@ -558,11 +558,11 @@ struct xex2_header {
 
 struct xex2_page_descriptor {
   union {
+    xe::be<uint32_t> value;  // 0x0
     struct {
       xex2_section_type info : 4;
       uint32_t page_count : 28;
     };
-    xe::be<uint32_t> value;  // 0x0
   };
   char data_digest[0x14];  // 0x4
 };

src/xenia/kernel/xam/user_profile.h

@@ -36,13 +36,13 @@ class UserProfile {
       INVALID = 0xFF,
     };
     union Key {
+      uint32_t value;
       struct {
         uint32_t id : 14;
         uint32_t unk : 2;
         uint32_t size : 12;
         uint32_t type : 4;
       };
-      uint32_t value;
     };
     uint32_t setting_id;
     Type type;

src/xenia/kernel/xnotifylistener.cc

@@ -32,7 +32,7 @@ void XNotifyListener::Initialize(uint64_t mask, uint32_t max_version) {
 }
 
 void XNotifyListener::EnqueueNotification(XNotificationID id, uint32_t data) {
-  auto key = XNotificationKey{id};
+  auto key = XNotificationKey(id);
   // Ignore if the notification doesn't match our mask.
   if ((mask_ & uint64_t(1ULL << key.mask_index)) == 0) {
     return;

src/xenia/kernel/xnotifylistener.h

@@ -13,6 +13,7 @@
 #include <memory>
 #include <unordered_map>
 
+#include "xenia/base/assert.h"
 #include "xenia/base/mutex.h"
 #include "xenia/base/threading.h"
 #include "xenia/kernel/xobject.h"
@@ -22,21 +23,21 @@ namespace xe {
 namespace kernel {
 
 union XNotificationKey {
+  XNotificationID id;
   struct {
     uint32_t local_id : 16;
     uint32_t version : 9;
     uint32_t mask_index : 6;
     uint32_t : 1;
   };
-  XNotificationID id;
 
-  static constexpr XNotificationID get_id(uint8_t mask_index,
-                                          uint16_t local_id) {
-    XNotificationKey key = {};
-    key.mask_index = mask_index;
-    key.local_id = local_id;
-    return key.id;
+  constexpr XNotificationKey(
+      XNotificationID notification_id = XNotificationID(0))
+      : id(notification_id) {
+    static_assert_size(*this, sizeof(id));
   }
+
+  constexpr operator XNotificationID() { return id; }
 };
 
 class XNotifyListener : public XObject {