Fix invoke call on Clang (possibly a compiler bug)

[alvinhochun]

For unknown reasons, Clang resolves the invoke call (in winrt::impl::promise_base::Completed and winrt::impl::promise_base::set_completed) to std::invoke instead of winrt::impl::invoke, which breaks exception handling and causes some disconnected.cpp tests to crash. After changing the call to specify the namespace, 4 more tests in disconnected.cpp now passes on Clang.

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To demonstrate the issue, I modified the generated winrt/Windows::Foundation.h and duplicated line 3765 (winrt::impl::promise_base::set_completed), and changed it so that one call specifies the namespace and the other doesn't. The disassembly shows how the name resolution of the two calls differ (this is with clang+mingw but the same happens with clang+msvc):

** 3763             if (handler)
   3764             {

    0x1ea95c <+156>: leal   -0x8(%ebp), %ecx
    0x1ea95f <+159>: calll  0x155e70                  ; winrt::Windows::Foundation::IUnknown::operator bool at base.h:2139
    0x1ea964 <+164>: testb  $0x1, %al
    0x1ea966 <+166>: jne    0x1ea971                  ; <+177> at Windows.Foundation.h
    0x1ea96c <+172>: jmp    0x1ea9a7                  ; <+231> at Windows.Foundation.h:3768:9

   1    // WARNING: Please don't edit this file. It was generated by C++/WinRT v2.3.4.5

    0x1ea971 <+177>: movl   -0x14(%ebp), %ecx

-> 3765                 invoke(handler, *this, status);

->  0x1ea974 <+180>: movl   %esp, %eax
    0x1ea976 <+182>: leal   -0xc(%ebp), %edx
    0x1ea979 <+185>: movl   %edx, 0x8(%eax)
    0x1ea97c <+188>: movl   %ecx, 0x4(%eax)
    0x1ea97f <+191>: leal   -0x8(%ebp), %ecx
    0x1ea982 <+194>: movl   %ecx, (%eax)
    0x1ea984 <+196>: calll  0x1ea9c0                  ; std::__1::invoke<winrt::Windows::Foundation::AsyncActionWithProgressCompletedHandler<int>&, winrt::impl::promise_base<std::__1::coroutine_traits<winrt::Windows::Foundation::IAsyncActionWithProgress<int>>::promise_type, winrt::Windows::Foundation::IAsyncActionWithProgress<int>, int>&, winrt::Windows::Foundation::AsyncStatus&> at invoke.h:530
    0x1ea989 <+201>: jmp    0x1ea98e                  ; <+206> at Windows.Foundation.h

   1    // WARNING: Please don't edit this file. It was generated by C++/WinRT v2.3.4.5

    0x1ea98e <+206>: movl   -0x14(%ebp), %ecx

** 3766                 ::winrt::impl::invoke(handler, *this, status);
   3767             }

    0x1ea991 <+209>: leal   -0x8(%ebp), %edx
    0x1ea994 <+212>: leal   -0xc(%ebp), %eax
    0x1ea997 <+215>: movl   %edx, (%esp)
    0x1ea99a <+218>: movl   %ecx, 0x4(%esp)
    0x1ea99e <+222>: movl   %eax, 0x8(%esp)
    0x1ea9a2 <+226>: calll  0x1ea9f0                  ; winrt::impl::invoke<winrt::Windows::Foundation::AsyncActionWithProgressCompletedHandler<int>, winrt::impl::promise_base<std::__1::coroutine_traits<winrt::Windows::Foundation::IAsyncActionWithProgress<int>>::promise_type, winrt::Windows::Foundation::IAsyncActionWithProgress<int>, int>, winrt::Windows::Foundation::AsyncStatus> at base.h:5859

** 3768         }

[kennykerr]

Sweet, thanks!

[kennykerr]

/azp run

[azure-pipelines]

No pipelines are associated with this pull request.

[dmachaj]

This crash has started affecting some of our components that are on an older cppwinrt version. For unknown reasons std::invoke is now called by MSVC in addition to the previous Clang problems. This manifests as a crash.

Fortunately the fix is available for more than a year. We just need to update cppwinrt versions in a lot more places to get it.