Ignore SQLiteException if UDC database is locked.

src/AddIns/Misc/UsageDataCollector/UsageDataCollector/UsageDataSessionWriter.cs

@@ -68,8 +68,14 @@ namespace ICSharpCode.UsageDataCollector
 			lock (lockObj) {
 				if (isDisposed)
 					return;
+				try {
 					try {
 						FlushOutstandingChanges();
+					} catch (SQLiteException ex) {
+						// Ignore exception if the DB file is locked
+						if (ex.ErrorCode != SQLiteErrorCode.Locked)
+							throw;
+					}
 				} catch (Exception ex) {
 					Action<Exception> onException = this.OnException;
 					if (onException != null)