Chrome扩展程序 - 生成按键

Question

我正在尝试编写一个生成模拟键盘事件的chrome扩展程序。

This question explains how to generate the keyboard event，但是当我在内容脚本上运行它时会产生以下错误：

error: Refused to execute inline script because it violates the following Content Security Policy directive: "script-src 'self' chrome-extension-resource:".

我该怎么做才能解决这个问题？

这是我的manifest.xml

{
  "name": "2048 forever",
  "description": "SOLVES EVERYTHING",
  "version": "2.0",
  "permissions": [
    "activeTab"
  ],
  "web_accessible_resources": ["keyboard.js"],
  "background": {
    "scripts": ["background.js"],
    "persistent": false
  },
  "browser_action": {
    "default_title": "Solve the things"
  },
  "manifest_version": 2
}

background.js包含：

chrome.browserAction.onClicked.addListener(function(tab) {
    console.log('Turning ' + tab.url + ' red!');

    chrome.tabs.executeScript({
        code: 'document.body.style.backgroundColor="red"'
    });

    triggerKeyEvent(document.body, 38);
});


function triggerKeyEvent(element, charCode) {
    // We cannot pass object references, so generate an unique selector
    var attribute = 'robw_' + Date.now();
    element.setAttribute(attribute, '');
    var selector = element.tagName + '[' + attribute + ']';

    var s = document.createElement('script');
    s.textContent = '(' + function(charCode, attribute, selector) {
        // Get reference to element...
        var element = document.querySelector(selector);
        element.removeAttribute(attribute);

        // Create KeyboardEvent instance
        var event = document.createEvent('KeyboardEvents');
        event.initKeyboardEvent(
            /* type         */ 'keydown',
            /* bubbles      */ true,
            /* cancelable   */ false,
            /* view         */ window,
            /* keyIdentifier*/ '',
            /* keyLocation  */ 0,
            /* ctrlKey      */ false,
            /* altKey       */ false,
            /* shiftKey     */ false,
            /* metaKey      */ false,
            /* altGraphKey  */ false
        );
        // Define custom values
        // This part requires the script to be run in the page's context
        var getterCode = {get: function() {return charCode}};
        var getterChar = {get: function() {return String.fromCharCode(charCode)}};
        Object.defineProperties(event, {
            charCode: getterCode,
            which: getterChar,
            keyCode: getterCode, // Not fully correct
            key: getterChar,     // Not fully correct
            char: getterChar
        });

        element.dispatchEvent(event);
    } + ')(' + charCode + ', "' + attribute + '", "' + selector + '")';

    console.log('text content: ' + s.textContent);

    (document.head||doc.documentElement).appendChild(s);
    s.parentNode.removeChild(s);
}