Created attachment 90323 [details]
Add some temporary debugging information to kservice

It looks like KService doesn't properly validate the metadata in KPluginInfo.
It loads also plugins where the metadata are completely empty.

How to reproduce this/get debugging information:
- install via GHNS a new plasma wallpaper which comes as single picture (without metadata.desktop) or just drop a picture to ~/.local/share/wallpapers
- apply the attached patch to kservice
- restart plasmashell & monitor its output
- open plasmashell's "Desktop Settings" dialog
- hover the previously installed wallpaper

Every time the wallpaper is hovered, the following debug output will be shown by plasmashell:

Constructing a KPluginInfo object from old style JSON. Please use kcoreaddons_desktop_to_json() for "" instead of kservice_desktop_to_json() in your CMake code.
obj: {
                                              "KPlugin": {
                                                  "Authors": {
                                                  },
                                                  "Dependencies": [
                                                  ],
                                                  "Description": "",
                                                  "EnabledByDefault": false,
                                                  "Name": "",
                                                  "ServiceTypes": [
                                                  ]
                                              }
                                          }
plugin: {
                                              "Authors": {
                                              },
                                              "Dependencies": [
                                              ],
                                              "Description": "",
                                              "EnabledByDefault": false,
                                              "Name": "",
                                              "ServiceTypes": [
                                              ]
                                          }

This indicates that at this point, completely empty metadata are loaded which shouldn't pass validation.