pseduo-destructor tests

[Aaron Ballman]

I noticed that clang\test\CXX\basic\basic.lookup\basic.lookup.qual\p6-0x.cpp
is XFAILed for all targets with the comment "Our C++0x doesn't
currently have specialized destructor name handling, since the
specification is still in flux."

That seems a bit outdated. From looking at the standard, I believe
this test should be unXFAILed, the comment removed, and
expected-no-diagnostics added to the test. The contents of the test
are:

struct C {
  typedef int I;
};

typedef int I1, I2;
extern int* p;
extern int* q;

void f() {
  p->C::I::~I();
  q->I1::~I2();
}

struct A {
  ~A();
};

typedef A AB;
int main() {
  AB *p;
  p->AB::~AB();
}

Any disagreement with that direction?

~Aaron