functionObjects: Removed the redundant "viable" member function

Construction failure and recovery is not handled with exceptions in functionObjectList

src/postProcessing/functionObjects/field/fieldValues/cellSource/cellSource.C

@@ -218,23 +218,16 @@ Foam::functionObjects::fieldValues::cellSource::cellSource
     weightFieldName_("none"),
     writeVolume_(dict.lookupOrDefault("writeVolume", false))
 {
+    if (!isA<fvMesh>(obr))
+    {
+        FatalErrorInFunction
+            << "objectRegistry is not an fvMesh" << exit(FatalError);
+    }
+
     read(dict);
 }
 
 
-bool Foam::functionObjects::fieldValues::cellSource::viable
-(
-    const word& name,
-    const objectRegistry& obr,
-    const dictionary& dict,
-    const bool loadFromFiles
-)
-{
-    // Construction is viable if the available mesh is an fvMesh
-    return isA<fvMesh>(obr);
-}
-
-
 // * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
 
 Foam::functionObjects::fieldValues::cellSource::~cellSource()

src/postProcessing/functionObjects/field/fieldValues/cellSource/cellSource.H

@@ -250,16 +250,6 @@ public:
             const bool loadFromFiles = false
         );
 
-        //- Return true if the construction of this functionObject is viable
-        //  i.e. the prerequisites for construction are available
-        static bool viable
-        (
-            const word& name,
-            const objectRegistry&,
-            const dictionary&,
-            const bool loadFromFiles = false
-        );
-
 
     //- Destructor
     virtual ~cellSource();