[EXPLORER] Restore windows on second click of Show Desktop button (#7184)

On the second click on "Show desktop" button, the minimized windows
are not restored, because after the first click, and the addition to
`CSimpleArray<MINWNDPOS> g_MinimizedAll`, a call to `RestoreMinimizedNonTaskWnds()`
via `HSHELL_WINDOWACTIVATED` message clears the list of minimized windows.

Don't empty `g_MinimizedAll` while processing HSHELL_WINDOWCREATED or
HSHELL_WINDOWACTIVATED messages (bDestroyed=FALSE).

Empty `g_MinimizedAll` only when SendPulseToTray is called with bDestroyed=TRUE.

Addendum to e6bced7a35 and 70d7009ad9. CORE-19703 CORE-15369

base/shell/explorer/traywnd.cpp

@@ -3049,9 +3049,9 @@ HandleTrayContextMenu:
             }
         }
 
-        g_MinimizedAll.RemoveAll();
-
-        if (!bDestroyed)
+        if (bDestroyed)
+            g_MinimizedAll.RemoveAll();
+        else
             ::SetForegroundWindow(hwndActive);
     }