Re #0. Remove useless log cache that bypasses COW mechanism.

Framework/DataObjects/inc/MantidDataObjects/PeaksWorkspace.h

@@ -283,11 +283,6 @@ private:
 
   /// Coordinates
   Kernel::SpecialCoordinateSystem m_coordSystem;
-
-  // adapter for logs() function, which create reference to this class itself
-  // and does not allow to delete the shared pointers,
-  // returned by logs() function when they go out of scope
-  API::LogManager_sptr m_logCash;
 };
 
 /// Typedef for a shared pointer to a peaks workspace.

Framework/DataObjects/src/PeaksWorkspace.cpp

@@ -877,15 +877,9 @@ PeaksWorkspace::getSpecialCoordinateSystem() const {
 struct NullDeleter {
   template <typename T> void operator()(T *) {}
 };
-/**Get access to shared pointer containing workspace porperties, cashes the
- shared pointer
- into internal class variable to not allow shared pointer being deleted */
+/**Get access to shared pointer containing workspace porperties */
 API::LogManager_sptr PeaksWorkspace::logs() {
-  if (m_logCash)
-    return m_logCash;
-
-  m_logCash = API::LogManager_sptr(&(this->mutableRun()), NullDeleter());
-  return m_logCash;
+  return API::LogManager_sptr(&(this->mutableRun()), NullDeleter());
 }
 
 /** Get constant access to shared pointer containing workspace porperties;