Add enableReferrers and enableHyperlinkAuditing to contentSettings.misc API.

chrome/test/data/extensions/api_test/content_settings/standard/test.html

 <script>
 // Content settings API test
 // Run with browser_tests --gtest_filter=ExtensionApiTest.ContentSettings
 
 var cs = chrome.experimental.contentSettings;
 function expect(expected, message) {
   return chrome.test.callbackPass(function(value) {
     chrome.test.assertEq(expected, value, message);
   });
 }
 chrome.test.runTests([
   function getBlockThirdPartyCookies() {
     cs.misc.blockThirdPartyCookies.get(
         {}, 
         expect({ 'value': true,
                  'levelOfControl': "ControllableByThisExtension" },
                "third-party cookies should be blocked"));
   },
+  function getEnableReferrers() {
+    cs.misc.enableReferrers.get(
+        {},
+        expect({ 'value': false,
+                 'levelOfControl': "ControllableByThisExtension" },
+               "referrers should be disabled"));
+  },
   function setBlockThirdPartyCookies() {
     cs.misc.blockThirdPartyCookies.set(
         {'value': false},
         chrome.test.callbackPass());
+  },
+  function setEnableReferrers() {
+    cs.misc.enableReferrers.set(
+        {'value': true},
+        chrome.test.callbackPass());
   }
 ]);
 </script>