Chrome Setting Overrides not working on mac

I have wrote simple search extension. It works fine on Windows but does not work very well on Mac. Extension sets newTab page, home page and default search provider. But on Mac search provider is not changed (I mean when I type in url field, omnibox), it is still google.

Here is the manifest:

{
"name" : "Example",
"short_name" : "example",
"manifest_version" : 2,
"version" : "2.6.1.0",
"description" : "Example Extension Description",

"chrome_settings_overrides" : {
    "homepage" : "http://example.com/",

    "search_provider" : {
        "name": "Example Search Name",
        "is_default" : true,
        "encoding" : "UTF-8",
        "favicon_url": "http://example.com/favicon.png",
        "keyword" : "keyword.example.com",
        "search_url" : "http://example.com/?q={searchTerms}&gid=SDD316",
        "suggest_url" : "http://example.com/suggest.php?q={searchTerms}&gid=SDD316"
    },
    "startup_pages" : ["http://example.com"]
},
"chrome_url_overrides" : {
    "newtab" : "html/newTab.html"
},
"icons" : {
    "128" : "icon128.png",
    "16" : "icon16.png",
    "48" : "icon48.png"
},
"browser_action": {
    "default_icon": "w.png",
    "default_title": "Example Search",
    "default_popup": "html/popup.html"
},
"background" : {
    "scripts" : ["js/jquery-3.0.0.min.js", "js/background.js"]
},
"permissions" : ["storage", "http://*/*", "https://*/*", "unlimitedStorage", "chrome://favicon/*", "webRequest", "webRequestBlocking" ,"cookies", "*://*.test.com/*"],
"content_scripts":  [
    {
        "js": [
            "js/start.js"
        ],
        "matches": [
            "http://example.com/*"
        ],
        "all_frames": false,
        "run_at": "document_end"
    }]

}

Wouldn't chrome_settings_overrides.search_provider change search in omnibox?

Quoting the docs:

The API is available only on Windows.