Revert "Initial checkin of accessibility extensions."

ui/accessibility/extensions/highcontrast/background.js

-// Copyright (c) 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-function injectContentScripts() {
-  chrome.windows.getAll({'populate': true}, function(windows) {
-    for (var i = 0; i < windows.length; i++) {
-      var tabs = windows[i].tabs;
-      for (var j = 0; j < tabs.length; j++) {
-        var url = tabs[j].url;
-        if (url.indexOf('chrome') == 0 || url.indexOf('about') == 0) {
-          continue;
-        }
-        chrome.tabs.insertCSS(
-            tabs[j].id,
-            {file: 'highcontrast.css', allFrames: true});
-        chrome.tabs.executeScript(
-            tabs[j].id,
-            {file: 'highcontrast.js', allFrames: true});
-      }
-    }
-  });
-}
-
-function updateTabs() {
-  var msg = {
-    'enabled': getEnabled()
-  };
-  chrome.windows.getAll({'populate': true}, function(windows) {
-    for (var i = 0; i < windows.length; i++) {
-      var tabs = windows[i].tabs;
-      for (var j = 0; j < tabs.length; j++) {
-        var url = tabs[j].url;
-        if (isDisallowedUrl(url)) {
-          continue;
-        }
-        var msg = {
-          'enabled': getEnabled(),
-          'scheme': getSiteScheme(siteFromUrl(url))
-        };
-        chrome.tabs.sendRequest(tabs[j].id, msg);
-      }
-    }
-  });
-}
-
-function toggleEnabled() {
-  setEnabled(!getEnabled());
-  updateTabs();
-}
-
-function toggleSite(url) {
-  var site = siteFromUrl(url);
-  var scheme = getSiteScheme(site);
-  if (scheme > 0) {
-    scheme = 0;
-  } else if (getDefaultScheme() > 0) {
-    scheme = getDefaultScheme();
-  } else {
-    scheme = DEFAULT_SCHEME;
-  }
-  setSiteScheme(site, scheme);
-  updateTabs();
-}
-
-function init() {
-  injectContentScripts();
-  updateTabs();
-
-  chrome.extension.onRequest.addListener(
-      function(request, sender, sendResponse) {
-        if (request['toggle_global']) {
-          toggleEnabled();
-        }
-        if (request['toggle_site']) {
-          toggleSite(sender.tab ? sender.tab.url : 'www.example.com');
-        }
-        if (request['init']) {
-          var scheme = getDefaultScheme();
-          if (sender.tab) {
-            scheme = getSiteScheme(siteFromUrl(sender.tab.url));
-          }
-          var msg = {
-            'enabled': getEnabled(),
-            'scheme': scheme
-          };
-          sendResponse(msg);
-        }
-      });
-
-  document.addEventListener('storage', function(evt) {
-    updateTabs();
-  }, false);
-
-  if (navigator.appVersion.indexOf('Mac') != -1) {
-    chrome.browserAction.setTitle({'title': 'High Contrast (Cmd+Shift+F11)'});
-  }
-}
-
-init();