Initial checkin of accessibility extensions.

ui/accessibility/extensions/highcontrast/common.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.
+
+var DEFAULT_SCHEME = 3;
+var MAX_SCHEME = 5;
+
+function $(id) {
+  return document.getElementById(id);
+}
+
+function getEnabled() {
+  var result = localStorage['enabled'];
+  if (result === 'true' || result === 'false') {
+    return (result === 'true');
+  }
+  localStorage['enabled'] = 'true';
+  return true;
+}
+
+function setEnabled(enabled) {
+  localStorage['enabled'] = enabled;
+}
+
+function getKeyAction() {
+  var keyAction = localStorage['keyaction'];
+  if (keyAction == 'global' || keyAction == 'site') {
+    return keyAction;
+  }
+  keyAction = 'global';
+  localStorage['keyaction'] = keyAction;
+  return keyAction;
+}
+
+function setKeyAction(keyAction) {
+  if (keyAction != 'global' && keyAction != 'site') {
+    keyAction = 'global';
+  }
+  localStorage['keyaction'] = keyAction;
+}
+
+function getDefaultScheme() {
+  var scheme = localStorage['scheme'];
+  if (scheme >= 0 && scheme <= MAX_SCHEME) {
+    return scheme;
+  }
+  scheme = DEFAULT_SCHEME;
+  localStorage['scheme'] = scheme;
+  return scheme;
+}
+
+function setDefaultScheme(scheme) {
+  if (!(scheme >= 0 && scheme <= MAX_SCHEME)) {
+    scheme = DEFAULT_SCHEME;
+  }
+  localStorage['scheme'] = scheme;
+}
+
+function getSiteScheme(site) {
+  var scheme = getDefaultScheme();
+  try {
+    var siteSchemes = JSON.parse(localStorage['siteschemes']);
+    scheme = siteSchemes[site];
+    if (!(scheme >= 0 && scheme <= MAX_SCHEME)) {
+      scheme = getDefaultScheme();
+    }
+  } catch (e) {
+    scheme = getDefaultScheme();
+  }
+  return scheme;
+}
+
+function setSiteScheme(site, scheme) {
+  if (!(scheme >= 0 && scheme <= MAX_SCHEME)) {
+    scheme = getDefaultScheme();
+  }
+  var siteSchemes = {};
+  try {
+    siteSchemes = JSON.parse(localStorage['siteschemes']);
+    siteSchemes['www.example.com'] = getDefaultScheme();
+  } catch (e) {
+    siteSchemes = {};
+  }
+  siteSchemes[site] = scheme;
+  localStorage['siteschemes'] = JSON.stringify(siteSchemes);
+}
+
+function resetSiteSchemes() {
+  var siteSchemes = {};
+  localStorage['siteschemes'] = JSON.stringify(siteSchemes);
+}
+
+function siteFromUrl(url) {
+  var a = document.createElement('a');
+  a.href = url;
+  return a.hostname;
+}
+
+function isDisallowedUrl(url) {
+  return url.indexOf('chrome') == 0 || url.indexOf('about') == 0;
+}