Inject multiple scripts on Chrome Extension pageAction

injectMultiple.js

function createSrcCall(tabId, src, callback) {
    return function () {
        if (callback !== undefined) {
            chrome.tabs.executeScript(tabId, {file: src}, callback);
        } else {
            chrome.tabs.executeScript(tabId, {file: src});
        }
    };
}

function injectScripts(tabId, srcs) {
    var i, callback;

    srcs.reverse();

    for (i = 0; i < srcs.length; i++) {
        callback = createSrcCall(tabId, srcs[i], callback);
    }
    callback();
}

chrome.pageAction.onClicked.addListener(function (tab) {
    // Scripts in execution order for cognitive ease, reversed in injectScripts
    injectScripts(tab.id, ["jquery.min.js", "another.min.js", "final.js"]);
});