regedit: Correctly export REG_DWORD values with no data.

programs/regedit/regproc.c

@@ -1345,8 +1345,12 @@ static void export_data(FILE *fp, WCHAR *value_name, DWORD value_len, DWORD type
         export_string_data(&buf, data, size);
         break;
     case REG_DWORD:
-        export_dword_data(&buf, data);
-        break;
+        if (size)
+        {
+            export_dword_data(&buf, data);
+            break;
+        }
+        /* fall through */
     case REG_NONE:
     case REG_EXPAND_SZ:
     case REG_BINARY:

programs/regedit/tests/regedit.c

@@ -3588,7 +3588,7 @@ static void test_export(void)
     RegCloseKey(hkey);
 
     run_regedit_exe("regedit.exe /e file.reg HKEY_CURRENT_USER\\" KEY_BASE);
-    ok(compare_export("file.reg", empty_hex_test, TODO_REG_COMPARE), "compare_export() failed\n");
+    ok(compare_export("file.reg", empty_hex_test, 0), "compare_export() failed\n");
 
     delete_key(HKEY_CURRENT_USER, KEY_BASE);
 
@@ -3605,7 +3605,7 @@ static void test_export(void)
     RegCloseKey(hkey);
 
     run_regedit_exe("regedit.exe /e file.reg HKEY_CURRENT_USER\\" KEY_BASE);
-    ok(compare_export("file.reg", empty_hex_test2, TODO_REG_COMPARE), "compare_export() failed\n");
+    ok(compare_export("file.reg", empty_hex_test2, 0), "compare_export() failed\n");
 
     delete_key(HKEY_CURRENT_USER, KEY_BASE);