win32u: Use user message packing for WM_STYLECHANGING.

dlls/user32/winproc.c

@@ -854,14 +854,12 @@ BOOL unpack_message( HWND hwnd, UINT message, WPARAM *wparam, LPARAM *lparam,
     case WM_WINDOWPOSCHANGING:
     case WM_WINDOWPOSCHANGED:
     case WM_HELP:
+    case WM_STYLECHANGING:
+    case WM_STYLECHANGED:
         break;
     case WM_NOTIFY:
         /* WM_NOTIFY cannot be sent across processes (MSDN) */
         return FALSE;
-    case WM_STYLECHANGING:
-    case WM_STYLECHANGED:
-        minsize = sizeof(STYLESTRUCT);
-        break;
     case WM_GETDLGCODE:
         if (*lparam)
         {
@@ -1103,6 +1101,8 @@ BOOL WINAPI User32CallWindowProc( struct win_proc_params *params, ULONG size )
         case WM_WINDOWPOSCHANGED:
         case WM_COPYDATA:
         case WM_HELP:
+        case WM_STYLECHANGING:
+        case WM_STYLECHANGED:
         {
             LRESULT *result_ptr = (LRESULT *)buffer - 1;
             *result_ptr = result;

dlls/win32u/message.c

@@ -536,6 +536,10 @@ static BOOL unpack_message( HWND hwnd, UINT message, WPARAM *wparam, LPARAM *lpa
         memcpy( &ps->hi, &hi, sizeof(hi) );
         break;
     }
+    case WM_STYLECHANGING:
+    case WM_STYLECHANGED:
+        minsize = sizeof(STYLESTRUCT);
+        break;
     case WM_WINE_SETWINDOWPOS:
     {
         WINDOWPOS wp;
@@ -1348,6 +1352,10 @@ size_t user_message_size( UINT message, WPARAM wparam, LPARAM lparam, BOOL other
     case WM_HELP:
         size = sizeof(HELPINFO);
         break;
+    case WM_STYLECHANGING:
+    case WM_STYLECHANGED:
+        size = sizeof(STYLESTRUCT);
+        break;
     }
 
     return size;
@@ -1476,6 +1484,9 @@ static void copy_user_result( void *buffer, size_t size, LRESULT result, UINT me
     case WM_WINDOWPOSCHANGING:
         copy_size = sizeof(WINDOWPOS);
         break;
+    case WM_STYLECHANGING:
+        copy_size = sizeof(STYLESTRUCT);
+        break;
     default:
         return;
     }
@@ -1503,9 +1514,6 @@ static void copy_reply( LRESULT result, HWND hwnd, UINT message, WPARAM wparam,
     case CB_GETCOMBOBOXINFO:
         copy_size = sizeof(COMBOBOXINFO);
         break;
-    case WM_STYLECHANGING:
-        copy_size = sizeof(STYLESTRUCT);
-        break;
     case WM_GETDLGCODE:
         if (lparam) copy_size = sizeof(MSG);
         break;

dlls/win32u/tests/win32u.c

@@ -1656,6 +1656,8 @@ static void test_wndproc_hook(void)
     static const COPYDATASTRUCT cds3_in = { .dwData = 2, .lpData = (void *)0xdeadbeef };
     static const COPYDATASTRUCT cds4_in = { .cbData = 2 };
     static const COPYDATASTRUCT cds5_in = { .lpData = (void *)0xdeadbeef };
+    static const STYLESTRUCT style_in = { .styleOld = 1, .styleNew = 2 };
+    static const STYLESTRUCT style_out = { .styleOld = 10, .styleNew = 20 };
 
     static const struct lparam_hook_test lparam_hook_tests[] =
     {
@@ -1795,6 +1797,16 @@ static void test_wndproc_hook(void)
             .lparam_size = sizeof(cds5_in), .lparam = &cds5_in, .poison_lparam = TRUE,
             .check_size = sizeof(cds5_in),
         },
+        {
+            "WM_STYLECHANGING", WM_STYLECHANGING,
+            .lparam_size = sizeof(style_in), .lparam = &style_in, .change_lparam = &style_out,
+            .check_size = sizeof(style_in)
+        },
+        {
+            "WM_STYLECHANGED", WM_STYLECHANGED,
+            .lparam_size = sizeof(style_in), .lparam = &style_in, .poison_lparam = TRUE,
+            .check_size = sizeof(style_in),
+        },
         /* messages that don't change lparam */
         { "WM_USER", WM_USER },
         { "WM_NOTIFY", WM_NOTIFY },

dlls/wow64win/user.c

@@ -827,6 +827,7 @@ static size_t packed_result_32to64( UINT message, WPARAM wparam, const void *par
     case WM_GETTEXT:
     case WM_ASKCBFORMATNAME:
     case WM_GETMINMAXINFO:
+    case WM_STYLECHANGING:
         break;
 
     default: