codedFixedValueFvPatchField: Updated and simplified using the new CodedBase class

reducing code duplication and maintenance overhead.

src/finiteVolume/fields/fvPatchFields/derived/codedFixedValue/codedFixedValueFvPatchFields.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2020 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -27,6 +27,20 @@ License
 #include "addToRunTimeSelectionTable.H"
 #include "volFields.H"
 
+// * * * * * * * * * * * * Private Static Data Members * * * * * * * * * * * //
+
+defineTypeName(Foam::codedFixedValueFvPatchFieldBase);
+
+template<>
+const Foam::wordList
+Foam::CodedBase<Foam::codedFixedValueFvPatchFieldBase>::codeKeys_ =
+{
+    "code",
+    "codeInclude",
+    "localCode"
+};
+
+
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 namespace Foam