Installer/vboxapisetup.py: Delete the IHost and IVirtualBox objects once no

longer needed and before shutting down XPCOM (setup.py:oVBoxMgr.deinit() ->
xpcom._xpcom.DeinitCOM() -> deinitVBoxPython() -> NS_ShutdownXPCOM()) which
shuts down the interface manager (XPTI_FreeInterfaceInfoManager() ->
xptiInterfaceInfoManager::FreeInterfaceInfoManager()).  Otherwise during
garbage collection later when these objects are deleted we will call back
into the interface manager (PyXPCOM_TypeObject::Py_dealloc ->
Py_nsIInterfaceInfo::~Py_nsIInterfaceInfo -> Py_nsISupports::~Py_nsISupports()
-> Py_nsISupports::SafeRelease() -> ... -> xptiInterfaceInfo::Release() ->
xptiInterfaceInfoManager::GetInfoMonitor() ->
xptiInterfaceInfoManager::GetInterfaceInfoManagerNoAddRef()) after it
has been free'd and trigger an exception and python stack trace.


svn:sync-xref-src-repo-rev: r173369

Author: paulsonx

src/VBox/Installer/common/vboxapisetup.py

@@ -140,6 +140,8 @@ def testVBoxAPI():
             raise Exception('Host platform invalid!')
         print("Testing VirtualBox Python bindings successful: Detected VirtualBox %s (%d)" % (oVBox.version, oHost.architecture))
         _ = oVBox.getMachines()
+        del oHost
+        del oVBox
         oVBoxMgr.deinit()
         del oVBoxMgr
     except ImportError as exc: