notifications: add support for unpackaged apps and protocol activation

src/common/com_object_factory.h

@@ -0,0 +1,60 @@
+#pragma once
+
+#include <Unknwn.h>
+#include <winrt/base.h>
+#include <atomic>
+
+template<typename T>
+class com_object_factory : public IClassFactory
+{
+public:
+    HRESULT __stdcall QueryInterface(const IID & riid, void** ppv) override
+    {
+        static const QITAB qit[] = {
+            QITABENT(com_object_factory, IClassFactory),
+            { 0 }
+        };
+        return QISearch(this, qit, riid, ppv);
+    }
+
+    ULONG __stdcall AddRef() override
+    {
+        return ++_refCount;
+    }
+
+    ULONG __stdcall Release() override
+    {
+        LONG refCount = --_refCount;
+        return refCount;
+    }
+
+    HRESULT __stdcall CreateInstance(IUnknown* punkOuter, const IID & riid, void** ppv)
+    {
+        *ppv = nullptr;
+        HRESULT hr;
+        if (punkOuter)
+        {
+            hr = CLASS_E_NOAGGREGATION;
+        }
+        else
+        {
+            T* psrm = new (std::nothrow) T();
+            HRESULT hr = psrm ? S_OK : E_OUTOFMEMORY;
+            if (SUCCEEDED(hr))
+            {
+                hr = psrm->QueryInterface(riid, ppv);
+                psrm->Release();
+            }
+            return hr;
+        }
+        return hr;
+    }
+
+    HRESULT __stdcall LockServer(BOOL)
+    {
+        return S_OK;
+    }
+
+private:
+    std::atomic<long> _refCount;
+};