Some minor clean ups for multi threading

Database/AthenaPOOL/AthenaPoolCnvSvc/AthenaPoolCnvSvc/AthenaPoolConverter.h

@@ -124,7 +124,7 @@ protected: // data
    const Token*          m_i_poolToken;
 
    typedef std::mutex CallMutex;
-   mutable CallMutex m_conv_mut;
+   CallMutex m_conv_mut;
 };
 
 #endif

Database/AthenaPOOL/AthenaPoolCnvSvc/AthenaPoolCnvSvc/T_AthenaPoolCustCnv.icc

@@ -169,8 +169,10 @@ T_AthenaPoolCustCnv<TRANS, PERS>::PoolToDataObject(DataObject*& pObj,
 // the object that will be read next.  Required by compareClassGuid()
 template <class TRANS, class PERS>
 inline void T_AthenaPoolCustCnv<TRANS, PERS>::setToken(const std::string& token_str) {
-   if (this->m_i_poolToken == nullptr) this->m_i_poolToken = new Token;
-   const_cast<Token*>(this->m_i_poolToken)->fromString(token_str);
+   delete this->m_i_poolToken; this->m_i_poolToken = nullptr;
+   Token* token = new Token;
+   token->fromString(token_str);
+   this->m_i_poolToken = token; token = nullptr;
    m_classID = this->m_i_poolToken->classID();
 }
 //__________________________________________________________________________

Database/AthenaPOOL/AthenaPoolCnvSvc/src/AthenaPoolCnvSvc.h

@@ -214,7 +214,7 @@ private: // properties
 
    /// Output FileNames to be associated with Stream Clients
    StringArrayProperty m_streamClientFilesProp;
-   mutable std::vector<std::string>   m_streamClientFiles;
+   std::vector<std::string>   m_streamClientFiles;
 
    /// MaxFileSizes, vector with maximum file sizes for Athena POOL output files
    StringArrayProperty m_maxFileSizes;
@@ -225,7 +225,7 @@ private: // properties
    /// default = false.
    BooleanProperty m_persSvcPerOutput;
    unsigned outputContextId(const std::string& outputConnection);
-   mutable std::mutex  m_mutex;  // mutable so const functions can lock
+   std::mutex  m_mutex;
   
    /// SkipFirstChronoCommit, boolean property to skip the first commit in the chrono stats so the first
    /// container being committed to disk is not 'tainted' with the POOL overhead

Database/AthenaPOOL/PoolSvc/src/PoolSvc.h

@@ -186,7 +186,7 @@ private: // data
    coral::Context*                                   m_context{nullptr};
    pool::IFileCatalog*                               m_catalog{nullptr};
    std::vector<pool::IPersistencySvc*>               m_persistencySvcVec;
-   mutable std::vector<CallMutex*>                   m_pers_mut;
+   std::vector<CallMutex*>                           m_pers_mut;
    std::map<std::string, unsigned int>               m_contextLabel;
    std::string                                       m_mainOutputLabel{};
    std::map<unsigned int, unsigned int>              m_contextMaxFile;