Add color enhancer as a chromium accessibility extensions.

ui/accessibility/extensions/colorenhancer/src/common.js

Index: ui/accessibility/extensions/colorenhancer/src/common.js
diff --git a/ui/accessibility/extensions/colorenhancer/src/common.js b/ui/accessibility/extensions/colorenhancer/src/common.js
new file mode 100644
index 0000000000000000000000000000000000000000..ed8a2972b94c7a50471dcf92308c8f54b612888e
--- /dev/null
+++ b/ui/accessibility/extensions/colorenhancer/src/common.js
@@ -0,0 +1,230 @@
+// Copyright (c) 2014 The Chromium Authors. All rights reserved.

[kevers, 2015/03/09 13:56:59]

Please drop (c) here and in other headers.  Also, as this is a new file in the
Chrome codebase, the year should be updated to 2015.

[Peter Wen, 2015/03/09 21:35:56]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+
+// ======= Utils =======
+
+function $(id) {
+  return document.getElementById(id);
+}
+
+
+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;
+}
+
+
+// ======= Delta setting =======
+
+var DEFAULT_DELTA = 1.0;
+var LOCAL_STORAGE_TAG_DELTA = "cvd_delta";
+var LOCAL_STORAGE_TAG_SITE_DELTA = "cvd_deltas";
+
+
+function validDelta(delta) {
+  return delta >= 0 && delta <= 1;
+}
+
+
+function getDefaultDelta() {
+  var delta = localStorage[LOCAL_STORAGE_TAG_DELTA];
+  if (validDelta(delta)) {
+    return delta;
+  }
+  delta = DEFAULT_DELTA;
+  localStorage[LOCAL_STORAGE_TAG_DELTA] = delta;
+  return delta;
+}
+
+
+function setDefaultDelta(delta) {
+  if (!validDelta(delta)) {
+    delta = DEFAULT_DELTA;
+  }
+  localStorage[LOCAL_STORAGE_TAG_DELTA] = delta;
+}
+
+
+function getSiteDelta(site) {
+  var delta = getDefaultDelta();
+  try {
+    var siteDeltas = JSON.parse(localStorage[LOCAL_STORAGE_TAG_SITE_DELTA]);
+    delta = siteDeltas[site];
+    if (!validDelta(delta)) {
+      delta = getDefaultDelta();
+    }
+  } catch (e) {
+    delta = getDefaultDelta();
+  }
+  return delta;
+}
+
+
+function setSiteDelta(site, delta) {
+  if (!validDelta(delta)) {
+    delta = getDefaultDelta();
+  }
+  var siteDeltas = {};
+  try {
+    siteDeltas = JSON.parse(localStorage[LOCAL_STORAGE_TAG_SITE_DELTA]);
+  } catch (e) {
+    siteDeltas = {};
+  }
+  siteDeltas[site] = delta;
+  localStorage[LOCAL_STORAGE_TAG_SITE_DELTA] = JSON.stringify(siteDeltas);
+}
+
+
+function resetSiteDeltas() {
+  var siteDeltas = {};
+  localStorage[LOCAL_STORAGE_TAG_SITE_DELTA] = JSON.stringify(siteDeltas);
+}
+
+
+// ======= Severity setting =======
+
+var DEFAULT_SEVERITY = 1.0;
+var LOCAL_STORAGE_TAG_SEVERITY = "cvd_severity";
+var LOCAL_STORAGE_TAG_SITE_SEVERITY = "cvd_severities";
+
+
+function validSeverity(severity) {
+  return severity >= 0 && severity <= 1;
+}
+
+
+function getDefaultSeverity() {
+  var severity = localStorage[LOCAL_STORAGE_TAG_SEVERITY];
+  if (validSeverity(severity)) {
+    return severity;
+  }
+  severity = DEFAULT_SEVERITY;
+  localStorage[LOCAL_STORAGE_TAG_SEVERITY] = severity;
+  return severity;
+}
+
+
+function setDefaultSeverity(severity) {
+  if (!validSeverity(severity)) {
+    severity = DEFAULT_SEVERITY;
+  }
+  localStorage[LOCAL_STORAGE_TAG_SEVERITY] = severity;
+}
+
+
+// TODO(mustaq): Remove site-specific severity setting.
+function getSiteSeverity(site) {
+  var severity = getDefaultSeverity();
+  try {
+    var siteSeverities =
+        JSON.parse(localStorage[LOCAL_STORAGE_TAG_SITE_SEVERITY]);
+    severity = siteSeverities[site];
+    if (!validSeverity(severity)) {
+      severity = getDefaultSeverity();
+    }
+  } catch (e) {
+    severity = getDefaultSeverity();
+  }
+  return severity;
+}
+
+
+function setSiteSeverity(site, severity) {
+  if (!validSeverity(severity)) {
+    severity = getDefaultSeverity();
+  }
+  var siteSeverities = {};
+  try {
+    siteSeverities = JSON.parse(localStorage[LOCAL_STORAGE_TAG_SITE_SEVERITY]);
+  } catch (e) {
+    siteSeverities = {};
+  }
+  siteSeverities[site] = severity;
+  localStorage[LOCAL_STORAGE_TAG_SITE_SEVERITY] =
+      JSON.stringify(siteSeverities);
+}
+
+
+function resetSiteSeverities() {
+  var siteSeverities = {};
+  localStorage[LOCAL_STORAGE_TAG_SITE_SEVERITY] =
+      JSON.stringify(siteSeverities);
+}
+
+
+// ======= Type setting =======
+
+var DEFAULT_TYPE = "type_a";
+var LOCAL_STORAGE_TAG_TYPE = "cvd_type";
+
+
+function validType(type) {
+  return type === "type_a" || type === "type_b" || type === "type_c";
+}
+
+
+function getDefaultType() {
+  var type = localStorage[LOCAL_STORAGE_TAG_TYPE];
+  if (validType(type)) {
+    return type;
+  }
+  type = DEFAULT_TYPE;
+  localStorage[LOCAL_STORAGE_TAG_TYPE] = type;
+  return type;
+}
+
+
+function setDefaultType(type) {
+  if (!validType(type)) {
+    type = DEFAULT_TYPE;
+  }
+  localStorage[LOCAL_STORAGE_TAG_TYPE] = type;
+}
+
+
+// ======= Simulate setting =======
+
+var DEFAULT_SIMULATE = false;
+var LOCAL_STORAGE_TAG_SIMULATE = "cvd_simulate";
+
+
+function validSimulate(simulate) {
+  return simulate == true || simulate == false;
+}
+
+
+function getDefaultSimulate() {
+  var simulate = localStorage[LOCAL_STORAGE_TAG_SIMULATE];
+
+  //Make it a boolean if possible
+  if (simulate === "true") {
+    simulate = true;
+  } else if (simulate === "false") {
+    simulate = false;
+  } else {
+    simulate = "undef";
+  }
+
+  if (validSimulate(simulate)) {
+    return simulate;
+  }
+  simulate = DEFAULT_SIMULATE;
+  localStorage[LOCAL_STORAGE_TAG_SIMULATE] = simulate;
+  return simulate;
+}
+
+
+function setDefaultSimulate(simulate) {
+  if (!validSimulate(simulate)) {
+    simulate = DEFAULT_SIMULATE;
+  }
+  localStorage[LOCAL_STORAGE_TAG_SIMULATE] = simulate;
+}