[Sema] Fix PR35832 - Ambiguity accessing anonymous struct/union with multiple bases.
Summary:
Currently clang doesn't do qualified lookup when building indirect field decl references. This causes ambiguity when the field is in a base class to which there are multiple valid paths even though a qualified name is used.
For example:
```
class B {
protected:
int i;
union { int j; };
};
class X : public B { };
class Y : public B { };
class Z : public X, public Y {
int a() { return X::i; } // works
int b() { return X::j; } // fails
};
```
Reviewers: rsmith, aaron.ballman, rjmccall
Reviewed By: rjmccall
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D45411
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@329519
91177308-0d34-0410-b5e6-
96231b3b80d8