COMP: ambiguity in IOobject::writeHeader

- a C-string is interpreted as a bool instead of as a word,
  so remove default parameter to eliminate ambiguity

src/OpenFOAM/db/IOobject/IOobject.H

@@ -520,12 +520,11 @@ public:
         //- Write the standard end file divider
         static Ostream& writeEndDivider(Ostream& os);
 
-        //- Write header with current type().
-        //  Optionally without arch information when ASCII
-        bool writeHeader(Ostream& os, const bool noArchAscii=false) const;
+        //- Write header with current type() and arch information
+        bool writeHeader(Ostream& os) const;
 
-        //- Write header with override of type.
-        //  Optionally without arch information when ASCII
+        //- Write header with override of type and optionally without
+        //- arch information in ASCII
         bool writeHeader
         (
             Ostream& os,

src/OpenFOAM/db/IOobject/IOobjectWriteHeader.C

@@ -171,9 +171,9 @@ bool Foam::IOobject::writeHeader
 }
 
 
-bool Foam::IOobject::writeHeader(Ostream& os, const bool noArchAscii) const
+bool Foam::IOobject::writeHeader(Ostream& os) const
 {
-    return writeHeader(os, type(), noArchAscii);
+    return writeHeader(os, type());
 }