Sema: Diagnose inaccessible implicit property wrapper inits again

DeclContext::lookupQualified() no longer calls addImplicitContructors(),
so we have to do it ourselves here, otherwise we accept code that used
to be rejected in Swift 5.2.

Author: slavapestov

lib/Sema/TypeCheckPropertyWrapper.cpp

@@ -125,6 +125,8 @@ findSuitableWrapperInit(ASTContext &ctx, NominalTypeDecl *nominal,
     break;
   }
 
+  TypeChecker::addImplicitConstructors(nominal);
+
   nominal->lookupQualified(nominal, DeclNameRef::createConstructor(),
                            NL_QualifiedDefault, decls);
   for (const auto &decl : decls) {

test/SILGen/Inputs/property_wrappers_multifile_other.swift

@@ -7,6 +7,8 @@ public class MyClass {
 
 @propertyWrapper
 public struct PropertyWrapper {
+  public init() { }
+
   public var projectedValue: PropertyWrapper {
     get {
       return self

test/SILGen/property_wrappers_final.swift

@@ -17,6 +17,8 @@ public class MyClass {
 
 @propertyWrapper
 public struct PropertyWrapper {
+  public init() { }
+
   public var projectedValue: PropertyWrapper {
     get {
       return self

test/decl/var/property_wrappers.swift

@@ -1934,5 +1934,10 @@ struct TestDefaultableIntWrapper {
   }
 }
 
-
-
+@propertyWrapper
+public struct NonVisibleImplicitInit {
+// expected-error@-1 3{{internal initializer 'init()' cannot have more restrictive access than its enclosing property wrapper type 'NonVisibleImplicitInit' (which is public)}}
+  public var wrappedValue: Bool {
+    return false
+  }
+}