shell32: Add implementation of IKnownFolder::GetCategory.

dlls/shell32/shellpath.c

@@ -3222,8 +3222,20 @@ static HRESULT WINAPI knownfolder_GetCategory(
     IKnownFolder *iface,
     KF_CATEGORY *pCategory)
 {
-    FIXME("%p\n", pCategory);
-    return E_NOTIMPL;
+    struct knownfolder *knownfolder = impl_from_IKnownFolder(iface);
+    HRESULT hr = S_OK;
+    DWORD dwSize, dwType;
+
+    TRACE("%p, %p\n", knownfolder, pCategory);
+
+    /* we can not get category for folder which is not registered */
+    if(!knownfolder->registryPath)
+        hr = E_FAIL;
+
+    if(SUCCEEDED(hr))
+        hr = HRESULT_FROM_WIN32(RegGetValueW(HKEY_LOCAL_MACHINE, knownfolder->registryPath, szCategory, RRF_RT_DWORD, &dwType, pCategory, &dwSize));
+
+    return hr;
 }
 
 static HRESULT WINAPI knownfolder_GetShellItem(

dlls/shell32/tests/shellpath.c

@@ -1176,9 +1176,7 @@ static void test_knownFolders(void)
                 if(SUCCEEDED(hr))
                 {
                     hr = IKnownFolder_GetCategory(folder, &cat);
-                    todo_wine
                     ok(hr == S_OK, "failed to get folder category: hr=0x%0x\n", hr);
-                    todo_wine
                     ok(cat == KF_CATEGORY_PERUSER, "invalid category returned: %d, while %d (KF_CATEGORY_PERUSER) expected\n", cat, KF_CATEGORY_PERUSER);
 
                     hr = IKnownFolder_GetId(folder, &folderId);