SharedResourcePointer: Allow objects with private constructors

modules/juce_core/memory/juce_SharedResourcePointer.h

@@ -153,7 +153,7 @@ private:
             if (auto locked = ptr.lock())
                 return locked;
 
-            auto shared = std::make_shared<SharedObjectType>();
+            const std::shared_ptr<SharedObjectType> shared (new SharedObjectType());
             ptr = shared;
             return shared;
         }

modules/juce_core/memory/juce_SharedResourcePointer_test.cpp

@@ -79,6 +79,18 @@ public:
 
             expect (SharedResourcePointer<Object>::getSharedObjectWithoutCreating() == std::nullopt);
         }
+
+        beginTest ("Create objects with private constructors");
+        {
+            class ObjectWithPrivateConstructor
+            {
+            private:
+                ObjectWithPrivateConstructor() = default;
+                friend SharedResourcePointer<ObjectWithPrivateConstructor>;
+            };
+
+            SharedResourcePointer<ObjectWithPrivateConstructor> instance;
+        }
     }
 };