Clang fails to resolve some names inside templates/lambdas under -fdelayed-template-parsing or --driver-mode=cl

[higher-performance]

Repro:

struct Outer
{
	template<class = void>
	static void foo()
	{
		struct S
		{
		};
		auto const g = []()
		{
			struct H
			{
				static void f()
				{
					typedef S S;  // error: unknown type name 'S'
				}
			};
		};
	}
};

int main()
{
	Outer().foo();
}

Both Clang and MSVC compile this fine with eager template parsing, but clang-cl fails to compile it due to delayed template parsing.

This makes clang-cl incompatible with MSVC.

Note that MSVC always handles this fine, regardless of /permissive[-] or /Zc:twoPhase[-].

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: None (higher-performance)

[Repro](https://godbolt.org/z/fM8rdcG4d): ``` struct Outer { template<class = void> static void foo() { struct S { }; auto const g = []() { struct H { static void f() { typedef S S; // error: unknown type name 'S' } }; }; } };

int main()
{
Outer().foo();
}

Both Clang and MSVC compile this fine with eager template parsing, but clang-cl fails to compile it due to delayed template parsing.

This makes clang-cl incompatible with MSVC.

Note that MSVC always handles this fine, regardless of `/permissive[-]` or `/Zc:twoPhase[-]`.
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