[Diagnostic] Fix regression in requirement diagnostics

Author: LucianoPAlmeida

lib/Sema/CSDiagnostics.cpp

@@ -282,6 +282,9 @@ ValueDecl *RequirementFailure::getDeclRef() const {
  return getAffectedDeclFromType(contextualTy);
  }
 
+ if (getLocator()->isFirstElement<LocatorPathElt::CoercionOperand>())
+ return getAffectedDeclFromType(getOwnerType());
+
  if (auto overload = getCalleeOverloadChoiceIfAvailable(getLocator())) {
  // If there is a declaration associated with this
  // failure e.g. an overload choice of the call

lib/Sema/CSGen.cpp

@@ -3329,9 +3329,8 @@ namespace {
  // bindings for the result of the coercion.
  if (repr &&
  repr->getKind() == TypeReprKind::ImplicitlyUnwrappedOptional) {
- auto *locatorIUO = CS.getConstraintLocator(expr);
- return createTypeVariableAndDisjunctionForIUOCoercion(toType,
- locatorIUO);
+ return createTypeVariableAndDisjunctionForIUOCoercion(
+ toType, CS.getConstraintLocator(expr));
  }
 
  return toType;