Introduce VPFullCluster class

Introduction of a second VPClass named VPFullCluster which includes the vector among the private members. Needed to later fix the issue of tracking efficiencies for TDR->master merge.

FYI : @cattanem , @sponce, @gligorov , @sneubert , @sstahl, @chasse , @graven , @adudziak , @fpolci , @gdujany

Event/DigiEvent/Event/VPFullCluster.h

+#ifndef RecEvent_VPFullCluster_H
+#define RecEvent_VPFullCluster_H 1
+
+// Include files
+#include "Kernel/VPChannelID.h"
+#include <boost/container/flat_map.hpp>
+#include <ostream>
+#include <vector>
+
+// Forward declarations
+
+namespace LHCb
+{
+
+  // Namespace for locations in TDS
+  namespace VPFullClusterLocation
+  {
+    static const std::string Default =   "Raw/VP/FullClusters";
+  }
+  class VPFullCluster final
+  {
+  public:
+    /// Constructor
+  VPFullCluster( const float xfraction, const float yfraction, const float x, const float y, const float z,
+		 const unsigned vpID )
+    : m_fx( xfraction ), m_fy( yfraction ), m_x( x ), m_y( y ), m_z( z ), m_vpID( vpID ), m_pixels({m_vpID})
+      {
+      }
+  VPFullCluster( const float xfraction, const float yfraction, const float x, const float y, const float z,
+		 const unsigned vpID, std::vector<VPChannelID>&& pixels )
+    : m_fx( xfraction ), m_fy( yfraction ), m_x( x ), m_y( y ), m_z( z ), m_vpID( vpID ), m_pixels( pixels )
+    {
+    }
+    
+    /// Return the cluster channelID = key
+    VPChannelID channelID() const noexcept { return m_vpID; }
+    
+    /// Print the cluster key = channelID
+    std::ostream& fillStream( std::ostream& s ) const
+      {
+	s << "{VPCluster's key: " << m_vpID << "}";
+	return s;
+    }
+    
+    /// Retrieve const  inter-pixel fraction
+    float xfraction() const noexcept { return m_fx; }
+    float yfraction() const noexcept { return m_fy; }
+    
+    /// Retrieve const  global x coordinate
+    float x() const noexcept { return m_x; }
+    
+    /// Retrieve const  global y coordinate
+    float y() const noexcept { return m_y; }
+    
+    /// Retrieve const  global z coordinate
+    float z() const noexcept { return m_z; }
+    
+    /// Retrieve const  vector of channel IDs
+    const std::vector<VPChannelID>& pixels() const noexcept { return m_pixels; }
+    
+    /// classID method, needed for MC linking. Returns the CLID of VPCluster for backward compatibility
+    static inline CLID classID() { return 4504; } //CLID_VPCluster
+    
+  private:
+    float m_fx;         ///< inter-pixel fraction in x coordinate
+    float m_fy;         ///< inter-pixel fraction in y coordinate
+    float m_x;          ///< global x coordinate
+    float m_y;          ///< global y coordinate
+    float m_z;          ///< global z coordinate
+    VPChannelID m_vpID; ///< channelID of cluster
+    std::vector<VPChannelID> m_pixels;
+    
+  }; // class VPFullCluster
+
+  /// lightweight container for VPFullCluster
+  typedef boost::container::flat_map<unsigned, VPFullCluster> VPFullClusters;
+  
+  inline std::ostream& operator<<( std::ostream& str, const VPFullCluster& obj ) { return obj.fillStream( str ); }
+  
+} // namespace LHCb;
+
+#endif /// DigiEvent_VPFullCluster_H