[KBSWITCH][NTUSER] Revert Shift+Alt handling

The current Shift+Alt handling is buggy. The keyboard won't work frequently.
It dislikes system-side Alt (VK_MENU) key handling.
It seems like Shift+Alt handling should be in kernel.
CORE-10667

base/applications/kbswitch/kbswitch.c

@@ -16,7 +16,6 @@
 PKBSWITCHSETHOOKS    KbSwitchSetHooks    = NULL;
 PKBSWITCHDELETEHOOKS KbSwitchDeleteHooks = NULL;
 UINT ShellHookMessage = 0;
-DWORD dwAltShiftHotKeyId = 0, dwShiftAltHotKeyId = 0;
 
 HINSTANCE hInst;
 HANDLE    hProcessHeap;
@@ -451,25 +450,6 @@ UpdateLanguageDisplayCurrent(HWND hwnd, WPARAM wParam)
     return UpdateLanguageDisplay(hwnd, hKL);
 }
 
-VOID DoRegisterAltShiftHotKeys(HWND hwnd)
-{
-    dwAltShiftHotKeyId = GlobalAddAtom(TEXT("ReactOS Alt+Shift"));
-    dwShiftAltHotKeyId = GlobalAddAtom(TEXT("ReactOS Shift+Alt"));
-
-    RegisterHotKey(hwnd, dwAltShiftHotKeyId, MOD_ALT | MOD_SHIFT, VK_SHIFT);
-    RegisterHotKey(hwnd, dwShiftAltHotKeyId, MOD_ALT | MOD_SHIFT, VK_MENU);
-}
-
-VOID DoUnregisterAltShiftHotKeys(HWND hwnd)
-{
-    UnregisterHotKey(hwnd, dwAltShiftHotKeyId);
-    UnregisterHotKey(hwnd, dwShiftAltHotKeyId);
-
-    GlobalDeleteAtom(dwAltShiftHotKeyId);
-    GlobalDeleteAtom(dwShiftAltHotKeyId);
-    dwAltShiftHotKeyId = dwShiftAltHotKeyId = 0;
-}
-
 LRESULT CALLBACK
 WndProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam)
 {
@@ -489,8 +469,6 @@ WndProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam)
 
             ActivateLayout(hwnd, ulCurrentLayoutNum);
             s_uTaskbarRestart = RegisterWindowMessage(TEXT("TaskbarCreated"));
-
-            DoRegisterAltShiftHotKeys(hwnd);
             break;
         }
 
@@ -499,14 +477,6 @@ WndProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam)
             return UpdateLanguageDisplay(hwnd, (HKL)lParam);
         }
 
-        case WM_HOTKEY:
-        {
-            if (wParam != dwAltShiftHotKeyId && wParam != dwShiftAltHotKeyId)
-                break;
-
-            /* FALL THROUGH */
-        }
-
         case WM_LOAD_LAYOUT:
         {
             ULONG uNextNum = GetNextLayout();
@@ -599,7 +569,6 @@ WndProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam)
 
         case WM_DESTROY:
         {
-            DoUnregisterAltShiftHotKeys(hwnd);
             DeleteHooks();
             DestroyMenu(s_hMenu);
             DeleteTrayIcon(hwnd);

win32ss/user/ntuser/hotkey.c

@@ -211,9 +211,7 @@ co_UserProcessHotKeys(WORD wVk, BOOL bIsDown)
         if (IsModifier)
         {
             /* Modifier key up -- modifier-only keys are triggered here */
-            pHotKey = IsHotKey(gfsModOnlyCandidate, wVk);
-            if (!pHotKey)
-                pHotKey = IsHotKey(gfsModOnlyCandidate, 0);
+            pHotKey = IsHotKey(gfsModOnlyCandidate, 0);
             gfsModOnlyCandidate = 0;
         }
         else