file UCP: Ensure myLocalTime is initialized

When a file's time is epoch (1970-01-01 00:00:00, i.e., TimeValue temp is all
zero) and the TZ is UTC or westward, osl_getLocalTimeFromSystemTime returns
false and leaves myLocalTime uninitialized.  That e.g. confuses getModuleByUrl
(scripting/source/pyprov/pythonscript.py), potentially re-loading a Python
script with epoch time (as happens e.g. for the share/Scripts/python/ files in
an xdg-app installation of LO) every time it is accessed, falsely assuming it
has changed on disk since last load.

Change-Id: I8d4228feb28e2697a7021e3488ae2c09e8439ed8

include/sal/log-areas.dox

@@ -351,6 +351,7 @@ certain functionality.
 @li @c ucb.ucp
 @li @c ucb.ucp.cmis
 @li @c ucb.ucp.ext
+@li @c ucb.ucp.file
 @li @c ucb.ucp.ftp
 @li @c ucb.ucp.gio
 @li @c ucb.ucp.gvfs

ucb/source/ucp/file/shell.cxx

@@ -2440,7 +2440,14 @@ shell::commit( const shell::ContentMap::iterator& it,
 
             // Convert system time to local time (for EA)
             TimeValue myLocalTime;
-            osl_getLocalTimeFromSystemTime( &temp, &myLocalTime );
+            if (!osl_getLocalTimeFromSystemTime( &temp, &myLocalTime ))
+            {
+                SAL_WARN(
+                    "ucb.ucp.file",
+                    "cannot convert (" << temp.Seconds << ", " << temp.Nanosec
+                        << ") to local time");
+                myLocalTime = temp;
+            }
 
             oslDateTime myDateTime;
             osl_getDateTimeFromTimeValue( &myLocalTime, &myDateTime );