Activity bar is rendered when a non-existent icon is used

[tsalinger]

testing #48407

"contributes": {
	"viewsContainers": {
		"activitybar": [
                        {
			    "id": "test",
			    "title": "Test",
			     "icon": "resources/test.svg"
		        }
                  ]
	}
}

1. Removing the icon property shows the following error notification:

property `icon` is mandatory and must be of type `string`

2. "icon": "somethingRandom", results in no error notification and there is an invisible activity bar that works as if there was an icon. The console shows GET file:///C:/vscode_projects/testplanItemsApril/test-view-containers--48407/ net::ERR_FILE_NOT_FOUND

I'm not sure if it makes sense to render an activity bar in the second case and maybe it should also show an error notification like in the first one.

[sandy081]

Yes & No. I think most of our contributions that need icons assume that icon exists. If icon does not exist, then an issue should be filed against extension.

[fabiospampinato]

I just stumbled into this, it would be nice if VSC saved us time warning us about a bad icon filepath.