neon commands cannot be aborted

See <http://lists.manyfish.co.uk/pipermail/neon/2013-February/001533.html> "Re:
About ne_set_read_timeout" for why ne_close_connection is not a solution here
(and currently would not work anyway, for the thread calling abort would block
on the aGlobalNeonMutex introduced with 510da291
"forced to make certain neon api calls thread-safe due to cups" until the
blocking thread was done with its neon call) and "a new, dedicated, thread-safe
ne_session_* API call will be needed to allow aborting of a running request."

So enable DAVResourceAccess::abort again and instead disable the underlying
NeonSession::abort.  i#106766 "Crash when cancelling extension update" does not
give any good rationale why DAVResourceAccess::abort had to be disabled, so it
might well have been because the underlying NeonSession::abort was bogus to
begin with.

Change-Id: If8293b93a960907726208bb2f93c375d83357ed3

sal/inc/sal/log-areas.dox

@@ -198,6 +198,7 @@ certain functionality.
 
 @li @c cmisucp
 @li @c ucb.ucp
+@li @c ucb.ucp.webdav
 
 @section unotools
 

ucb/source/ucp/webdav-neon/DAVResourceAccess.cxx

@@ -553,10 +553,8 @@ void DAVResourceAccess::GET(
 void DAVResourceAccess::abort()
   throw( DAVException )
 {
-    // 17.11.09 (tkr): abort currently disabled caused by issue i106766
-    // initialize();
-    // m_xSession->abort();
-    OSL_TRACE( "Not implemented. -> #i106766#" );
+    initialize();
+    m_xSession->abort();
 }
 
 //=========================================================================

ucb/source/ucp/webdav-neon/NeonSession.cxx

@@ -1657,11 +1657,7 @@ bool NeonSession::UNLOCK( NeonLock * pLock )
 void NeonSession::abort()
     throw ( DAVException )
 {
-    if ( m_pHttpSession )
-    {
-        osl::Guard< osl::Mutex > theGlobalGuard( aGlobalNeonMutex );
-        ne_close_connection( m_pHttpSession );
-    }
+    SAL_INFO("ucb.ucp.webdav", "neon commands cannot be aborted");
 }
 
 // -------------------------------------------------------------------