fdo#72163 belts and suspenders

1) Do not dispose m_xComposer, might still be used by our m_pCache

2) Do not create a new m_xComposer if the previous one will do, so
   that we do not gratiously use a different one than our m_pCache.

Change-Id: I6540c035c9159017c694b36e676721ec3e42db51

dbaccess/source/core/api/RowSet.cxx

@@ -2250,12 +2250,14 @@ sal_Bool ORowSet::impl_initComposer_throw( OUString& _out_rCommandToExecute )
     if ( !bUseEscapeProcessing )
         return bUseEscapeProcessing;
 
+    if (m_bCommandFacetsDirty)
+        m_xComposer = NULL;
+
     Reference< XMultiServiceFactory > xFactory( m_xActiveConnection, UNO_QUERY );
-    if ( xFactory.is() )
+    if ( !m_xComposer.is() && xFactory.is() )
     {
         try
         {
-            ::comphelper::disposeComponent( m_xComposer );
             m_xComposer.set( xFactory->createInstance( SERVICE_NAME_SINGLESELECTQUERYCOMPOSER ), UNO_QUERY_THROW );
         }
         catch (const Exception& ) { m_xComposer = NULL; }