Migrate extends2, etc. to extends

The explicit `extends2`, `extends3`, etc. classes are no longer required
and can be replaced by the variadic `extends`.

Calorimeter/CaloDetDescr/src/CaloSuperCellIDTool.h

@@ -27,7 +27,7 @@ class CaloCell_ID;
 class CaloCell_SuperCell_ID;
 
 class CaloSuperCellIDTool
-  : public extends1<AthAlgTool, ICaloSuperCellIDTool>
+  : public extends<AthAlgTool, ICaloSuperCellIDTool>
 {
 public:
   /**

Control/AthenaExamples/AthExHive/src/HiveExSvc.h

@@ -21,7 +21,7 @@
 #include <mutex>
 #include <memory>
 
-class HiveExSvc : public extends1<AthService,IHiveExSvc> {
+class HiveExSvc : public extends<AthService,IHiveExSvc> {
 
 public:
   HiveExSvc(const std::string& name, ISvcLocator* svc);

Control/AthenaExamples/AthExHive/src/ThreadInitTool.h

@@ -27,7 +27,7 @@
 //-------------------------------------------------------------------------------
 
 
-class ThreadInitTool: virtual public extends1<AthAlgTool, IThreadInitTool> {
+class ThreadInitTool: virtual public extends<AthAlgTool, IThreadInitTool> {
 
 public:
   ThreadInitTool( const std::string&, const std::string&, const IInterface* );

Control/AthenaExamples/AthExHive/src/condEx/ASCIICondDbSvc.h

@@ -17,7 +17,7 @@
 #include <vector>
 #include <mutex>
 
-class ASCIICondDbSvc: public extends1<AthService, IASCIICondDbSvc> {
+class ASCIICondDbSvc: public extends<AthService, IASCIICondDbSvc> {
 public:
 
   ASCIICondDbSvc(const std::string& name, ISvcLocator* svc);

Control/AthenaExamples/AthExHive/src/loopTest/HiveTool.h

@@ -13,7 +13,7 @@
 
 #include <string>
 
-class HiveTool : public extends1<AthAlgTool,IHiveTool> {
+class HiveTool : public extends<AthAlgTool,IHiveTool> {
 public:
   HiveTool( const std::string&, const std::string&, const IInterface* );
   virtual ~HiveTool();

Control/AthenaServices/src/AthTPCnvSvc.h

@@ -28,7 +28,7 @@ class ICLIDSvc;
 
 
 class AthTPCnvSvc
-  : public extends1<AthService, ITPCnvSvc>
+  : public extends<AthService, ITPCnvSvc>
 { 
  public: 
 

PhysicsAnalysis/D3PDMaker/D3PDMakerCoreComps/src/CollectionGetterRegistryTool.h

@@ -43,7 +43,7 @@ namespace D3PD {
  * collection getters are stateful.)
  */
 class CollectionGetterRegistryTool
-  : public extends1<AthAlgTool, ICollectionGetterRegistryTool>
+  : public extends<AthAlgTool, ICollectionGetterRegistryTool>
 {
 public:
   /**

PhysicsAnalysis/D3PDMaker/D3PDMakerCoreComps/src/ContainedAssociationFillerTool.h

@@ -50,7 +50,7 @@ namespace  D3PD {
  *                  Omitted if empty.
  */
 class ContainedAssociationFillerTool
-  : public extends1<AthAlgTool, IBlockFillerTool>, public AddVariable
+  : public extends<AthAlgTool, IBlockFillerTool>, public AddVariable
 {
 public:
   /**

PhysicsAnalysis/D3PDMaker/D3PDMakerCoreComps/src/ContainedMultiAssociationFillerTool.h

@@ -54,7 +54,7 @@ namespace  D3PD {
  *                  Omitted if empty.
  */
 class ContainedMultiAssociationFillerTool
-  : public extends1<AthAlgTool, IBlockFillerTool>, public AddVariable
+  : public extends<AthAlgTool, IBlockFillerTool>, public AddVariable
 {
 public:
   /**

PhysicsAnalysis/D3PDMaker/D3PDMakerCoreComps/src/ContainedVectorMultiAssociationFillerTool.h

@@ -57,7 +57,7 @@ namespace  D3PD {
  *                  Omitted if empty (default).
  */
 class ContainedVectorMultiAssociationFillerTool
-  : public extends1<VectorFillerToolBase, IBlockFillerTool>
+  : public extends<VectorFillerToolBase, IBlockFillerTool>
 {
 public:
   /**

PhysicsAnalysis/D3PDMaker/D3PDMakerCoreComps/src/FirstAssociationTool.h

@@ -35,7 +35,7 @@ class IMultiAssociationTool;
  * association tool by only using the first result from the association.
  */
 class FirstAssociationTool
-  : public extends1<AthAlgTool, ISingleAssociationTool>
+  : public extends<AthAlgTool, ISingleAssociationTool>
 {
 public:
   /**

PhysicsAnalysis/D3PDMaker/D3PDMakerCoreComps/src/IndexAssociationFillerTool.h

@@ -59,7 +59,7 @@ class ICollectionGetterTool;
  *   CollectionGetterRegistry - The ICollectionGetterRegistryTool instance.
  */
 class IndexAssociationFillerTool
-  : public extends1<AthAlgTool, IBlockFillerTool>, public AddVariable
+  : public extends<AthAlgTool, IBlockFillerTool>, public AddVariable
 {
 public:
   /**

PhysicsAnalysis/D3PDMaker/D3PDMakerCoreComps/src/IndexMultiAssociationFillerTool.h

@@ -61,7 +61,7 @@ class ICollectionRegistryTool;
  *   CollectionGetterRegistry - The ICollectionGetterRegistryTool instance.
  */
 class IndexMultiAssociationFillerTool
-  : public extends1<AthAlgTool, IBlockFillerTool>, public AddVariable
+  : public extends<AthAlgTool, IBlockFillerTool>, public AddVariable
 {
 public:
   /**

PhysicsAnalysis/D3PDMaker/D3PDMakerCoreComps/src/ObjFillerTool.h

@@ -47,7 +47,7 @@ class ID3PD;
  * to each.
  */
 class ObjFillerTool
-  : public extends2<AthAlgTool, IObjFillerTool, IIncidentListener>,
+  : public extends<AthAlgTool, IObjFillerTool, IIncidentListener>,
     public AddVariable
 {
 public:

PhysicsAnalysis/D3PDMaker/D3PDMakerCoreComps/src/VectorFillerTool.h

@@ -66,7 +66,7 @@ class ID3PD;
  * to each.
  */
 class VectorFillerTool
-  : public extends2<VectorFillerToolBase, IObjFillerTool, IIncidentListener>
+  : public extends<VectorFillerToolBase, IObjFillerTool, IIncidentListener>
 {
 public:
   /**

PhysicsAnalysis/D3PDMaker/D3PDMakerCoreComps/src/VoidObjFillerTool.h

@@ -43,7 +43,7 @@ class ID3PD;
  * For each event, we loop over all block filler tools.
  */
 class VoidObjFillerTool
-  : public extends2<AthAlgTool, IObjFillerTool, IIncidentListener>,
+  : public extends<AthAlgTool, IObjFillerTool, IIncidentListener>,
     public AddVariable
 {
 public:

PhysicsAnalysis/D3PDMaker/D3PDMakerRoot/src/RootD3PDSvc.h

@@ -35,7 +35,7 @@ namespace D3PD {
  * @brief Service to create a root-based D3PD.
  */
 class RootD3PDSvc
-  : public extends1<AthService, ID3PDSvc>
+  : public extends<AthService, ID3PDSvc>
 {
 public:
   /**

PhysicsAnalysis/D3PDMaker/D3PDMakerUtils/D3PDMakerUtils/BlockFillerToolImpl.h

@@ -40,7 +40,7 @@ namespace D3PD {
  * interface.
  */       
 class BlockFillerToolImpl
-  : public extends1<AthAlgTool, IBlockFillerTool>, public AddVariable
+  : public extends<AthAlgTool, IBlockFillerTool>, public AddVariable
 {
 public:
   /**

PhysicsAnalysis/D3PDMaker/D3PDMakerUtils/D3PDMakerUtils/CollectionGetterToolImpl.h

@@ -38,7 +38,7 @@ namespace D3PD {
  * the pieces that don't depend on the template argument.
  */
 class CollectionGetterToolImpl
-  : public extends1<ObjGetterToolImpl, ICollectionGetterTool>
+  : public extends<ObjGetterToolImpl, ICollectionGetterTool>
 {
 public:
   /**

PhysicsAnalysis/D3PDMaker/D3PDMakerUtils/D3PDMakerUtils/MultiAssociationToolImpl.h

@@ -41,7 +41,7 @@ namespace D3PD {
  * be overridden if the tool should itself fill any tuple variables.
  */
 class MultiAssociationToolImpl
-  : public extends1<AthAlgTool, IMultiAssociationTool>,
+  : public extends<AthAlgTool, IMultiAssociationTool>,
     public AddVariable
 {
 public: