chromium/third_party/blink/web_tests/permissionclient/image-permissions.html

<!DOCTYPE html>
<script src='../resources/js-test.js'></script>
<script>
jsTestIsAsync = true;

description("Blocked images can be reloaded, so neither onload nor onerror is called. Only check here that onload is never called when image is blocked.");

document.write('<img src="resources/boston.gif" onload="loaded()">');

function loaded()
{
    debug("PASS: first image loaded");
    if (window.internals)
        internals.settings.setImagesEnabled(false);
    else
        debug("This test requires windows.internals, so it be can't run in a browser.");

    // Load an image not in cache.
    var img = document.createElement('img');
    img.onload = function () { log("FAIL: not cached image loaded"); }
    img.src = "resources/boston.gif?nocache";
    document.getElementById("img").appendChild(img);

    // Load an image from cache.
    var imgFromCache = document.createElement('img');
    imgFromCache.onload = function () { log("FAIL: image from cache loaded"); }
    imgFromCache.src = "resources/boston.gif";
    document.getElementById("img").appendChild(imgFromCache);

    // Add an iframe with an image.
    var iframe = document.createElement('iframe');
    iframe.src = "resources/image.html";
    document.getElementById("img").appendChild(iframe);

    setTimeout(finishJSTest, 0);
}
</script>
<div id="img"></div>