moc does not do macro substitution

Moc do macro substitution in preprocessor command (#if) but not for source code.

Original report:

moc does not notice the namespace and generates meta-object code that does not compile for the class declaration below:

#define NAMESPACE_BEGIN namespace test

NAMESPACE_BEGIN

class AnalogClock : public QWidget
{
Q_OBJECT

public:
AnalogClock(QWidget *parent = 0);

protected:
void paintEvent(QPaintEvent *event);
};

NAMESPACE_END