set print object on should affect MI varobjs (PR mi/13393)

[xgsa]

> What exactly is the nature of the change, as will be visible by GDB
> users?  With that information in hand, I could answer your questions.

That was the reply on the original patch, so I thought that I can omit 
the description, sorry.

That patch makes "set print object" option affect MI interface. Here is 
an example:

struct Base {
     Base() : a(1) {}
     virtual ~Base() {}  // Enforce type to have RTTI
     int a;
};

struct Derived : public Base {
     Derived() : b(2) {}
     int b;
};

int main() {
     Derived b;
     Base* aPtr = &b;
     return 0;                  // [1]
}


Start gdb in MI mode and run to line [1]. Make -var-create for aPtr. If 
"set print object" is "on" you will see the type Derived* for the 
created varobj.

See also more details here: 
http://sourceware.org/bugzilla/show_bug.cgi?id=13393


Thanks,
Anton