Density BC has type zeroGradient for all patches

[staneuski]

Environment	Parameter
Compiled using OpenFOAM	dev-48a3622
Product Version	v0.4.3-alpha
Commit	50de29e
Case \ File	createFields.H
Comments	Density constructor loop makes nothing. Also this forAll loop has no sense and any logical explanation. But without rhoBCTypes (when type calculatedis set for all density BC patches) the solution is unstable.

wordList rhoBCTypes
(
    p.boundaryField().size(),
    zeroGradientFvPatchScalarField::typeName
);

forAll(U.boundaryField(), patchi)
{
    if (U.boundaryField().types()[patchi] == zeroGradientFvPatchScalarField::typeName)
    {
        rhoBCTypes[patchi] = fixedValueFvPatchScalarField::typeName;
    }
}