VSCode add icons to Activity Bar

How can I add other extension icons to the Activity Bar ?
I want to add new custom icon, next to the source control and debug icons.
I read this page but did not understand.
I went to path C:\Users\Moh\AppData\Local\Programs\Microsoft VS Code\resources\app and added this configs to package.json:

// etc...
"author": {
  "name": "Microsoft Corporation"
},
"license": "MIT",
"main": "./out/main",

//***************//
// I added following lines:
"contributes": {
  "views": {
    "code-runner": [
      {
        "id": "codeRunner",
        "name": "Code Runner"
      }
    ]
  }
},

// etc...

But nothing changed.
Is my chosen path correct?
Is the written configuration correct?