Add sample extension that allows setting plugin-specific content settings.

chrome/common/extensions/docs/examples/extensions/plugin_settings/domui/js/util.js

Index: chrome/common/extensions/docs/examples/extensions/plugin_settings/domui/js/util.js
diff --git a/chrome/common/extensions/docs/examples/extensions/plugin_settings/domui/js/util.js b/chrome/common/extensions/docs/examples/extensions/plugin_settings/domui/js/util.js
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index 0000000000000000000000000000000000000000..1efbf1907f9ded5739a8ae3976f1971461de5337
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@@ -0,0 +1,151 @@
+// Copyright (c) 2011 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.
+
+/**
+ * The global object.
+ * @type {!Object}
+ */
+const global = this;
+
+/**
+ * Alias for document.getElementById.
+ * @param {string} id The ID of the element to find.
+ * @return {HTMLElement} The found element or null if not found.
+ */
+function $(id) {
+  return document.getElementById(id);
+}
+
+/**
+ * Calls chrome.send with a callback and restores the original afterwards.
+ * @param {string} name The name of the message to send.
+ * @param {!Array} params The parameters to send.
+ * @param {string} callbackName The name of the function that the backend calls.
+ * @param {!Function} The function to call.
+ */
+function chromeSend(name, params, callbackName, callback) {
+  var old = global[callbackName];
+  global[callbackName] = function() {
+    // restore
+    global[callbackName] = old;
+
+    var args = Array.prototype.slice.call(arguments);
+    return callback.apply(global, args);
+  };
+  chrome.send(name, params);
+}
+
+/**
+ * Generates a CSS url string.
+ * @param {string} s The URL to generate the CSS url for.
+ * @return {string} The CSS url string.
+ */
+function url(s) {
+  // http://www.w3.org/TR/css3-values/#uris
+  // Parentheses, commas, whitespace characters, single quotes (') and double
+  // quotes (") appearing in a URI must be escaped with a backslash
+  var s2 = s.replace(/(\(|\)|\,|\s|\'|\"|\\)/g, '\\$1');
+  // WebKit has a bug when it comes to URLs that end with \
+  // https://bugs.webkit.org/show_bug.cgi?id=28885
+  if (/\\\\$/.test(s2)) {
+    // Add a space to work around the WebKit bug.
+    s2 += ' ';
+  }
+  return 'url("' + s2 + '")';
+}
+
+/**
+ * Parses query parameters from Location.
+ * @param {string} s The URL to generate the CSS url for.
+ * @return {object} Dictionary containing name value pairs for URL
+ */
+function parseQueryParams(location) {
+  var params = {};
+  var query = unescape(location.search.substring(1));
+  var vars = query.split("&");
+  for (var i=0; i < vars.length; i++) {
+    var pair = vars[i].split("=");
+    params[pair[0]] = pair[1];
+  }
+  return params;
+}
+
+function findAncestorByClass(el, className) {
+  return findAncestor(el, function(el) {
+    if (el.classList)
+      return el.classList.contains(className);
+    return null;
+  });
+}
+
+/**
+ * Return the first ancestor for which the {@code predicate} returns true.
+ * @param {Node} node The node to check.
+ * @param {function(Node) : boolean} predicate The function that tests the
+ *     nodes.
+ * @return {Node} The found ancestor or null if not found.
+ */
+function findAncestor(node, predicate) {
+  var last = false;
+  while (node != null && !(last = predicate(node))) {
+    node = node.parentNode;
+  }
+  return last ? node : null;
+}
+
+function swapDomNodes(a, b) {
+  var afterA = a.nextSibling;
+  if (afterA == b) {
+    swapDomNodes(b, a);
+    return;
+  }
+  var aParent = a.parentNode;
+  b.parentNode.replaceChild(a, b);
+  aParent.insertBefore(b, afterA);
+}
+
+/**
+ * Disables text selection and dragging.
+ */
+function disableTextSelectAndDrag() {
+  // Disable text selection.
+  document.onselectstart = function(e) {
+    e.preventDefault();
+  }
+
+  // Disable dragging.
+  document.ondragstart = function(e) {
+    e.preventDefault();
+  }
+}
+
+// Handle click on a link. If the link points to a chrome: or file: url, then
+// call into the browser to do the navigation.
+document.addEventListener('click', function(e) {
+  // Allow preventDefault to work.
+  if (!e.returnValue)
+    return;
+
+  var el = e.target;
+  if (el.nodeType == Node.ELEMENT_NODE &&
+      el.webkitMatchesSelector('A, A *')) {
+    while (el.tagName != 'A') {
+      el = el.parentElement;
+    }
+
+    if ((el.protocol == 'file:' || el.protocol == 'about:') &&
+        (e.button == 0 || e.button == 1)) {
+      chrome.send('navigateToUrl', [
+        el.href,
+        el.target,
+        e.button,
+        e.altKey,
+        e.ctrlKey,
+        e.metaKey,
+        e.shiftKey
+      ]);
+      e.preventDefault();
+    }
+  }
+});