Qt: try to fix the crash on start

The changes on preferences association registration, seems to have
attacked the taskbar part

(cherry picked from commit 0dce302d4cb74f4f9a2ddebb4a5db315895d58ea)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

modules/gui/qt4/main_interface_win32.cpp

@@ -115,9 +115,11 @@ void MainInterface::createTaskBarButtons()
     FIXME:the play button's picture doesn't changed to pause when clicked
     */
 
-    CoInitializeEx( NULL, COINIT_MULTITHREADED );
+    HRESULT hr = CoInitializeEx( NULL, COINIT_MULTITHREADED );
+    if( hr == RPC_E_CHANGED_MODE )
+        hr = CoInitializeEx( NULL, COINIT_APARTMENTTHREADED );
 
-    if( S_OK == CoCreateInstance( CLSID_TaskbarList,
+    if( SUCCEEDED(hr) && S_OK == CoCreateInstance( CLSID_TaskbarList,
                 NULL, CLSCTX_INPROC_SERVER,
                 IID_ITaskbarList3,
                 (void **)&p_taskbl) )
@@ -186,7 +188,6 @@ void MainInterface::createTaskBarButtons()
         himl = NULL;
         p_taskbl = NULL;
     }
-
 }
 
 bool MainInterface::winEvent ( MSG * msg, long * result )