[clang] [Clang][Parse] Fix crash on a coroutine keyword in a mem-initializer (PR #218168)

[Corentin Jabot via cfe-commits]

================
@@ -1566,3 +1566,10 @@ void g() {
 }
 
 }
+
+namespace GH194298 {
+coro<promise_void> f1() : bar { co_await suspend_always{} }; // expected-error {{only constructors take base initializers}}
+coro<promise> f2() : bar { co_yield 0 }; // expected-error {{only constructors take base initializers}}
+coro<promise_void> f3() : bar { co_return }; // expected-error {{expected expression}} \
+                                             // expected-error {{only constructors take base initializers}}
+}
----------------
cor3ntin wrote:

Can you add tests for 
 - co_await in a function try blocks
 - the same tests as above for a member function

Thanks

https://github.com/llvm/llvm-project/pull/218168