msi: Allocate MSISCRIPT structure at package creation time.

dlls/msi/action.c

@@ -6394,7 +6394,6 @@ UINT MSI_InstallPackage( MSIPACKAGE *package, LPCWSTR szPackagePath,
 
     MSI_SetPropertyW(package, szAction, szInstall);
 
-    package->script = msi_alloc_zero(sizeof(MSISCRIPT));
     package->script->InWhatSequence = SEQUENCE_INSTALL;
 
     if (szPackagePath)

dlls/msi/package.c

@@ -969,6 +969,7 @@ UINT MSI_OpenPackageW(LPCWSTR szPackage, MSIPACKAGE **pPackage)
         MSI_SetPropertyW( package, OriginalDatabase, fullpath );
     }
 
+    package->script = msi_alloc_zero( sizeof(MSISCRIPT) );
     *pPackage = package;
 
     return ERROR_SUCCESS;