Issue with some Fonts

[ag-drivequant]

When we use some fonts like "Roboto", the placeholder uses "Times new roman" font instead.

The problem is related to this code snippet

    private func placeholderFontFromFont(_ font: UIFont) -> UIFont! {
        let smallerFont = UIFont(name: font.fontName, size: font.pointSize * placeholderFontScale)
        return smallerFont
    }

For "Roboto" Font, UIFont(name: font.fontName, size: font.pointSize) does not return the right expected Font.