clear chat history bug fix (2992786)

git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@4015 b45a01b8-16f6-495d-af2f-9b41ad6348cc

retroshare-gui/src/gui/im_history/IMHistoryWriter.cpp

@@ -77,3 +77,9 @@ bool IMHistoryWriter::write(QList<IMHistoryItem>& itemList, const QString fileNa
 
     return true;
 }
+
+bool IMHistoryWriter::remove(const QString &fileName){
+
+    return QFile::remove(fileName);
+
+}