Merge pull request swiftlang#32741 from xedin/rdar-55042628-5.3

[5.3][Sema] Mark the direct callee as being a callee for all ApplyExpr not just CallExpr

Author: xedin

lib/Sema/TypeCheckConstraints.cpp

@@ -1161,7 +1161,7 @@ namespace {
       ExprStack.pop_back();
 
       // Mark the direct callee as being a callee.
-      if (auto *call = dyn_cast<CallExpr>(expr))
+      if (auto *call = dyn_cast<ApplyExpr>(expr))
         markDirectCallee(call->getFn());
 
       // Fold sequence expressions.

test/Constraints/operator.swift

@@ -290,3 +290,9 @@ func rdar_62054241() {
     return arr.sorted(by: <) // expected-error {{no exact matches in reference to operator function '<'}}
   }
 }
+
+// SR-11399 - Operator returning IUO doesn't implicitly unwrap
+postfix operator ^^^
+postfix func ^^^ (lhs: Int) -> Int! { 0 }
+
+let x: Int = 1^^^